BEST 8K Series Classroom Funct...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$1,043.00
$660.82
BEST BEST 8K Series - Classroom Function (R) Single Cylinder Grade 1 Heavy Duty Knob Lock, SFIC Less Core BEST-8K-R

BEST 8K Series Classroom Function Single Cylinder Grade 1 Heavy Duty Knob Lock

(No reviews yet) Write a Review

Model: 8K37R4ASTK626
$1,043.00
$660.82
Selected Finish is
Selected Knob Style is
Selected Rose is
Selected Strike is

In Stock (leaves warehouse same day if ordered before 3pm ET)

$1,043.00
$660.82
Adding to cart… The item has been added
Free Shipping on orders over $199
We price match and offer bulk discounts! Click Add to Quote. It's quick and easy.
✨
Earn points with this purchase! You can redeem points for giftcards, iPads, XBox's and more. View Rewards
Free Keying on all locks
You may also like

BEST 8K Series Classroom Function Single Cylinder Grade 1 Heavy Duty Knob Lock

Premium Grade 1 Cylindrical Knob Lock for Heavy-Duty Commercial Applications

The BEST 8K Series delivers dependable security for high-traffic commercial environments with knobs machined from solid brass or bronze bar stock and a 2 1/16" diameter chassis designed to fit 2 1/8" door holes. This Grade 1 heavy-duty cylindrical knob lock features a 9/16" throw deadlocking latch with 2 3/4" standard backset and accommodates door thickness from 1 3/8" to 2" standard. The classroom function (R) provides single cylinder operation with SFIC core compatibility for quick, economical rekeying.

Professional Features & Benefits

  • Grade 1 Heavy-Duty Construction: Exceeds ANSI Grade 1 requirements with knobs machined from solid brass or bronze bar stock for exceptional durability in commercial applications.
  • Precision Door Compatibility: 2 1/16" diameter chassis fits 2 1/8" door holes with adjustable door thickness from 1 3/8" to 2" standard, plus special E trim available for 2 1/8" to 3" doors.
  • Enhanced Security Design: Keyed knob removable only after core removal to deter break-in attempts, with snap-on inside rose featuring no exposed screws for additional tamper resistance.
  • SFIC Core System: 7-pin housing accepts all BEST cores (less SFIC core) enabling quick, economical rekeying with BEST interchangeable core technology.
  • Smooth Operation Components: Steel retractor with low friction bearings and long bearing length in chassis provide smooth, wear-resistant operation throughout the lock’s service life.
  • Versatile Rose Options: Multiple rose configurations including round 3 3/4" diameter (A), round 2 9/16" diameter (C), and convex round 3 3/8" diameter (D) for various aesthetic and functional requirements.
  • Professional Strike Options: Standard STK strike (2 3/4" x 1 1/8") for 1 3/8" doors and S3 strike (4 7/8" x 1 1/4") for 1 3/4" doors, both conforming to ANSI standards.
  • Corrosion-Resistant Materials: Internal components are brass or corrosion-treated steel with brass or bronze roses reinforced with steel liner for long-term reliability.

Technical Specifications

  • Commercial/Residential: Commercial
  • Department: Door Hardware
  • Door Hand Direction: Non-Handed
  • Duty Level: Heavy Duty
  • Electronic: No
  • Grade: Grade 1
  • Handle Type: Knob
  • Keyed: Yes
  • Keyed Function: Single Cylinder
  • Product Attribute: Cylindrical Locks
  • Product Category: Mechanical Locks
  • Product Function: Classroom
  • Product Group: Mechanical Locks
  • Product Subgroup: Bored Locksets
  • Product Type: Knobsets
  • Series: 8K Series
  • Standard Cylinder: 7-pin housing, accepts all BEST cores (less SFIC core)
  • Subcategory: Bored Locksets

Installation & Operation

  1. Review manufacturer specifications and verify door preparation requirements including 2 1/8" bore hole, 1" edge hole for latch, and door thickness compatibility (1 3/8" to 2" standard).
  2. Use manufacturer-provided templates to mark mounting hole locations accurately on door and frame surfaces, ensuring proper backset alignment (2 3/4" standard).
  3. Prepare door by drilling required 2 1/8" diameter hole for chassis and 1" hole in door edge for latch housing.
  4. Install latch assembly with 9/16" throw deadlocking mechanism and secure chassis to door per manufacturer torque specifications.
  5. Mount appropriate rose configuration (A, C, or D style) and install knobs, ensuring rotating knob face is properly aligned for hand of door requirements.
  6. Test lock operation including key function, latch engagement, and knob rotation to verify proper installation and make final adjustments as needed. Refer to manufacturer documentation for complete installation details and troubleshooting.

Professional Applications

  • Educational Facilities and Classroom Security
  • Government and Military Buildings
  • Commercial Office Buildings
  • Healthcare Institutions
  • Industrial and Warehouse Facilities
  • Multi-Tenant Residential Properties
  • International Projects Requiring Heavy-Duty Hardware

Why Choose BEST Quality?

BEST 8K Series knob locks deliver professional-grade reliability with solid brass or bronze construction and Grade 1 certification that exceeds ANSI requirements for security and durability. The precision-machined components and corrosion-resistant internal parts ensure dependable performance in demanding commercial applications where long-term security and smooth operation are essential.

Product Specs

Series:
8K Series
Grade:
Grade 1
Duty Level:
Heavy Duty
Keyed Function:
Single Cylinder
Standard Cylinder:
7-pin housing, accepts all BEST cores (less SFIC core)
Product Group:
Mechanical Locks
Product Subgroup:
Bored Locksets
Product Type:
Knobsets
Subcategory:
Bored Locksets
Keyed:
Yes
Electronic:
No
Commercial/Residential:
Commercial
Handle Type:
Knob
Product Attribute:
Cylindrical Locks
Product Function:
Classroom
Door Hand Direction:
Non-Handed
Product Category:
Mechanical Locks
Department:
Door Hardware

BEST 8K37R4ASTK626 – Frequently Asked Questions

1) Will the BEST 8K classroom knob lock fit my existing 2-1/8 inch bored door prep?
Yes. The 8K chassis is 2-1/16 inches in diameter and drops into a standard 2-1/8 inch cross bore, with a 1 inch hole in the door edge for the latch and a 2-3/4 inch backset. If your door was previously prepped for any standard commercial cylindrical lockset, no new boring is needed.
2) What door thickness does the BEST 8K knob lock cover, and what do I order for a thicker door?
Standard 8K trim covers 1-3/8 inch through 2 inch doors, which takes in both the common 1-3/4 inch commercial door and older 1-3/8 inch interior doors. For anything from 2-1/8 up to 3 inches, special E trim is required. There is also a 3-3/8 inch concave thick door rose option when you are working past the standard range.
3) Does the BEST 8K knob lock come with a core, and which cores does it take?
It ships less core. The 8K has a 7-pin housing that accepts all BEST small format interchangeable cores, so you pin and stamp your own and key it into an existing BEST system. Budget a core per lock as a separate line, and note that the keyed knob only comes off after the core is pulled, which is part of the anti-pry design.
4) Which strike should I order with a BEST 8K lock for a 1-3/4 inch door?
For 1-3/4 inch doors, take the S3 ANSI strike at 4-7/8 x 1-1/4 inches. The standard STK strike at 2-3/4 x 1-1/8 inches is for 1-3/8 inch doors. Both conform to ANSI, so if your frame already carries an ANSI strike cutout the 4-7/8 inch lip fills it without frame work. The latch is a 9/16 inch throw deadlocking latch, so the strike lip and depth need to suit that projection.
5) I need a classroom lock but not a BEST keyway. What else is there?
The Dexter C2000 Series classroom cylindrical ball knob lock is the closer alternative if you do not run a BEST core system. It is Grade 2 rather than Grade 1 and covers 1-3/8 to 1-3/4 inch doors, so it fits a lighter opening and a thinner door range than the 8K. Choose it when the door does not need Grade 1 and you are not keying into a BEST SFIC system.
6) Will a BEST 8K replace a Grade 2 or Grade 3 knob lock already on my doors?
Usually yes on prep. Most Grade 2 and Grade 3 cylindrical knobsets sit in the same 2-1/8 inch bore with a 2-3/4 inch backset, which is what the 8K uses. Two things to check first: door thickness, since a lot of the lighter locks such as the Cal-Royal BER00 and the Pamex FTF cover only 1-3/8 to 1-3/4 inches while the 8K reaches 2 inches, and the strike, since the existing frame may carry a small 2-3/4 inch lip strike rather than an ANSI cutout. Order the strike that matches the frame you have, not the door.
7) Is there a classroom function knob lock other than the BEST 8K?
The Dexter C2000 Series classroom ball knob lock is the other keyed classroom knob in the group. It is a Grade 2 lock fitting doors 1-3/8 inch to 1-3/4 inch, with a non-clutching ball knob. The BEST 8K classroom knob is Grade 1 heavy duty and carries a 7-pin housing that accepts all BEST cores. So the decision comes down to whether the opening needs Grade 1 chassis rating and BEST small format core keying, or whether a Grade 2 classroom function on a standard 1-3/4 inch door is the right fit.
8) What is the closest Grade 1 heavy duty knob lock to the BEST 8K classroom lock if I need an interchangeable core?
The Falcon X101 is the closest match on construction: it is a Grade 1 heavy duty cylindrical knobset with an interchangeable core, and it covers doors from 1-3/8 inch to 2-1/4 inch. The difference is function. The BEST 8K in classroom function is keyed and single cylinder, while the X101 is a passage/hall/closet function, so it has no key control at all. If the door needs to be locked and unlocked with a key from the outside, the X101 does not do that job even though the chassis grade and core concept line up.
9) What Grade 1 knob lock should I use if the door needs a storeroom function instead of classroom?
The Sargent 8XG04 is a Grade 1 heavy duty storeroom/closet knob lock with a single cylinder and a 2-3/4 inch backset, which is the same backset the BEST 8K uses as standard. Storeroom keeps the outside knob locked at all times and the key retracts the latch; classroom, the function the 8K carries here, lets a key leave the outside knob unlocked for a period. Both are single cylinder, so trim on the inside stays free-egress in either case.
10) Can I put a Corbin Russwin CK4851 on a door where a BEST 8K classroom lock was specified?
Only if the function change is acceptable. The CK4851 is an entrance/office cylindrical knob lock with a Global knob and a conventional cylinder, covering doors 1-3/8 inch to 2 inch, the same door thickness range the BEST 8K handles as standard. The two differences that matter: entrance/office lets the inside button lock the outside knob so an occupant can secure the door without a key, while the 8K classroom function is keyed from the corridor side only, and the CK4851 takes a conventional cylinder while the 8K uses a 7-pin housing for BEST small format cores. On a campus keyed to BEST cores, that cylinder difference breaks the master key system.
11) Do I need to specify a hand when ordering a BEST 8K knob lock?
No. The 8K is non-handed and works on a left or right hand door out of the box. During install you only need to make sure the rotating knob face sits correctly for the hand of the door.
12) What backset options does the BEST 8K knob lock come in, and when do I need the 5 inch?
Two backsets are offered: 2-3/4 inch standard and 5 inch. Take 2-3/4 for ordinary commercial openings. The 5 inch backset is what you use when the knob has to sit further off the door edge, typically on a wide stile or a door with a lock rail that puts the knob into a glass or panel edge.
13) What knob styles, roses, and finishes are available on the BEST 8K so I can match my other doors?
Knobs come in round and tulip. Roses are 2-9/16 inch concave, 3-3/8 inch concave, 3-3/8 inch concave for thick doors, and 3-3/8 inch convex. Ten finishes are offered: 605 bright brass, 606 satin brass, 611 bright bronze, 612 satin bronze, 613 satin bronze oil-rubbed, 619 satin nickel, 625 bright chrome, 626 satin chrome, 626AM satin chrome antimicrobial, and 690 statuary dark bronze. If a building is standardized on 626, that is the usual commercial pick, and 626AM gets specified in healthcare where an antimicrobial coating is called out.
14) Is the BEST 8K knob lock Grade 1, and is that enough for a high traffic school or hospital corridor?
Grade 1, heavy duty, and built for commercial use, with knobs machined from solid brass or bronze bar stock and internal parts in brass or corrosion-treated steel. Roses carry a steel liner. Grade 1 is the top ANSI/BHMA cylindrical grade and is what gets specified for the highest traffic institutional openings, so it suits school corridors, healthcare, and government work.
15) What is the Grade 1 lever or storeroom equivalent if a knob will not work for my opening?
Knobs are still specified on plenty of commercial openings, but where a knob is not acceptable or the function is wrong, two Grade 1 heavy duty cylindrical alternatives sit alongside the 8K: the Sargent 8XG04 storeroom knob lock, single cylinder with a 2-3/4 inch backset, and the Falcon X101 heavy duty passage knobset with interchangeable core, which covers 1-3/8 to 2-1/4 inch doors and is fire rated. Take the 8XG04 when the door should stay locked outside at all times, and the X101 where the opening is a latch-only pass-through.
16) I only need a storeroom knob and Grade 1 is more than the opening calls for. What is the lighter option?
The Sargent 6G04 is a standard duty Grade 2 storeroom/closet knob lock with a single cylinder. It sits a grade below the BEST 8K, which is Grade 1 heavy duty, and it is a storeroom function rather than classroom. For an interior storage or utility door in a low traffic area where the key simply needs to retract a permanently locked outside knob, the 6G04 covers it; the 8K is the choice where the opening needs a Grade 1 chassis and BEST core keying.
17) What is a Grade 1 knob for a classroom door that does not need to be keyed?
Two Grade 1 non-keyed knobs cover that: the Schlage D10S passage latch with an Orbit knob, which is heavy duty Grade 1, and the Corbin Russwin CK4310 passage/closet lock, Grade 1 with a Global knob, fitting doors 1-3/8 inch to 2 inch. Both are latch-only, so the door pushes open from either side with no key. The BEST 8K classroom knob is keyed with a 7-pin housing that accepts all BEST cores, which is what you want when the room has to be secured; if a corridor or storage door only needs a latch, the passage versions do the job without any keying to manage.
18) Will a Kwikset 400P keyed entry knob work in place of a BEST 8K on a commercial door?
They are not interchangeable for a commercial opening. The Kwikset 400P-CP keyed entry knob is Grade 3 and fits doors 1-3/8 inch to 1-3/4 inch, in an entrance function. The BEST 8K is a Grade 1 heavy duty commercial classroom lock accepting BEST interchangeable cores. The 400P is built for residential and light interior use; on a high-traffic commercial door where the spec calls for Grade 1, it does not meet the requirement, and its cylinder will not join a BEST core keying system.
19) Which knob locks look like a classroom lock but will not secure the room?
Several knobs in the same shape and rose family have no locking function at all. The Bravura Biloxi dummy knobset and the Omnia 442/00 single dummy latchset are dummy trim, meaning the knob does not turn a latch. The Schlage A170 is a Grade 2 single dummy trim, heavy duty in build but still non-keyed dummy. The Emtek Arts and Crafts Hammered Egg dummy pair is likewise dummy trim sold as a pair. None of these will hold a door closed or lock it. The BEST 8K is a keyed classroom function lock with a deadlocking latch, which is what secures the opening; the dummy knobs are for inactive leaves and closet faces only.
20) Is the Sargent 28C-KNOB an alternative to a BEST 8K classroom lock?
No, they solve different problems even though both are classroom function. The Sargent 28C-KNOB is exit device trim with a knob and rose for 1-3/4 inch doors, meaning it mounts to an exit device rather than working as a lock on its own. The BEST 8K is a cylindrical knob lock with its own chassis and deadlocking latch for a bored door. If the door already has a panic bar, the 28C trim is what you order; if the door is a plain bored opening, the 8K is the lock.
21) I need a bathroom or bedroom knob to match the commercial knobs elsewhere in the building. What do I order instead of the classroom lock?
The classroom function of the BEST 8K is keyed and single cylinder, which is wrong for a bathroom. For a privacy opening, the Dexter C2000 Series privacy ball knob is a Grade 2 non-keyed privacy lock for doors 1-3/8 inch to 1-3/4 inch, and the Cal-Royal BER20 is a Grade 3 privacy knob with brass trim over the same door thickness range. Privacy function locks from the inside with a button or turn and releases from outside with an emergency tool rather than a key, which is what a restroom or bedroom door needs.
22) What is a fire rated knob lock alternative if I do not need Grade 1?
The Falcon W101 is a medium duty Grade 2 cylindrical knob lock with a fire rating and a 2-3/4 inch backset, the same standard backset the BEST 8K uses, so the door prep carries over. The function is the split: the W101 is passage/hall/closet, non-locking, while the 8K is a keyed classroom lock. On a rated corridor door that only needs a latch, the W101 works; where the rated door also has to be secured, stay with a keyed lock.
23) The BEST 8K only goes to 2 inch thick doors with standard trim. Is there a knob lock rated for a thicker door?
The Falcon X101 covers doors from 1-3/8 inch to 2-1/4 inch, the widest thickness range among the comparable knobsets, and it is a Grade 1 heavy duty knobset with an interchangeable core. Note that it is a passage function, so it does not lock. On the BEST 8K side, a 3-3/8 inch concave thick-door rose is offered for heavier doors, and the 8K remains the keyed option.
24) For standardizing knob hardware across a facility, which alternatives share the same Grade 1 level as the BEST 8K?
Four Grade 1 knobsets sit alongside the BEST 8K: the Sargent 8XG04 storeroom/closet single cylinder lock, the Falcon X101 heavy duty passage knobset with interchangeable core, the Schlage D10S passage latch with Orbit knob, and the Corbin Russwin CK4310 passage/closet lock. Between them they cover storeroom and passage functions at Grade 1, while the BEST 8K supplies the keyed classroom function. Standardizing on one manufacturer keeps the cylinder platform consistent, and the 8K carries a 7-pin housing for BEST cores across all of its finishes and roses.
25) Can the BEST 8K knob be pulled off or wrenched to defeat the lock?
The keyed knob cannot be removed until the core is pulled, so there is nothing to grab and twist off from outside with the core in place. The inside rose snaps on with no exposed screws, which removes the other obvious attack point. Retraction runs through a steel retractor on low friction bearings with a long bearing length in the chassis, which is what keeps the feel consistent after years of corridor traffic.
26) Is the BEST 8K classroom lock electrified or does it tie into an access control system?
It is a mechanical lock, not electronic. There is no wiring, no request-to-exit switch, and no card reader interface. If the opening needs to be released or monitored from a head end, this is not the lock for it.
27) Does a keyless combination knob lock replace a keyed classroom lock?
The Lockey 3830 is a mechanical keyless combination knob lock with an auto-locking passage function, fitting doors 1 3/16 inch to 2 inch. It removes keys from the opening entirely, which suits a door where issuing keys is the problem. It does not join a key system: the BEST 8K uses a 7-pin housing that accepts all BEST cores, so it stays on a facility master key with the rest of the building. Pick the 3830 where you want a standalone door with a code, and the 8K where the door has to be part of the master keying.
28) What is the difference between the Corbin Russwin CK4310 and CK4410 when replacing a heavy duty knob lock?
They are the same Global knob passage/closet lock at two build levels. The CK4310 is Grade 1 and fits doors 1-3/8 inch to 2 inch; the CK4410 is Grade 2 and fits 1-3/8 inch to 1-3/4 inch. Neither is keyed. If the door previously carried a Grade 1 heavy duty lock like the BEST 8K and now only needs a latch, the CK4310 keeps the chassis rating; the CK4410 is the lighter build for a thinner standard door.
29) I need a keyed entry knob in satin nickel that is not a full commercial Grade 1 lock. What are the options?
For a lighter keyed opening, the Callan Roland is a Grade 2 entrance knobset in US15 satin nickel, and the Callan Edgewood is a Grade 2 entrance knobset in the same family. Below that, the Cal-Royal BER00 is a Grade 3 entrance/office knob lock with a Kwikset keyway for doors 1-3/8 inch to 1-3/4 inch, and the Master Lock BC01 is a Grade 3 keyed entry biscuit knob. The BEST 8K offers 619 Satin Nickel among its finishes at Grade 1 with BEST core keying, which is the choice when the door has to stay on a commercial key system.
How fast can I get the BEST 8K37R4ASTK626 delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the continental U.S. Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit, reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the BEST 8K37R4ASTK626 come with a warranty?
Absolutely. The BEST 8K37R4ASTK626 is backed by a manufacturer’s warranty. For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the BEST 8K37R4ASTK626?
You can call, text, or email our expert support team for fast answers. We’re here to help with product selection, installation tips, and troubleshooting. Contact Us
Why buy the BEST 8K37R4ASTK626 from ZenSupply?
ZenSupply makes it easy to get the commercial door hardware you need—fast shipping, expert support, and rewards on every order. Our team is always ready to help you choose the right product for your project.
!