BEST 8K Series Entrance Functi...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$1,158.00
$643.33
BEST BEST 8K Series - Service Station Function (E) Single Cylinder Grade 1 Heavy Duty Knob Lock, SFIC Less Core BEST-8K-E

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

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Model: 8K37AB4ASTK626
$1,158.00
$643.33
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In Stock (leaves warehouse same day if ordered before 3pm ET)

$1,158.00
$643.33
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BEST 8K Series Entrance 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, adjustable door thickness from 1 3/8" to 2", and accepts all BEST interchangeable cores with 7-pin housing. Exceeds ANSI Grade 1 requirements for security and reliability in demanding commercial applications.

Professional Features & Benefits

  • Heavy-Duty Construction: Knobs machined from solid brass or bronze bar stock with 2 1/8" diameter and 2 7/8" projection for exceptional durability and professional appearance.
  • Grade 1 Performance: Exceeds ANSI Grade 1 requirements for security and reliability with 9/16" throw deadlocking latch and steel retractor with low friction bearings.
  • Flexible Door Compatibility: Adjustable for door thickness from 1 3/8" to 2" standard, with special E trim available for 2 1/8" to 3" doors.
  • Enhanced Security Design: Cores must be removed before keyed knobs to deter break-in attempts, with snap-on inside rose featuring no exposed screws for tamper resistance.
  • BEST Interchangeable Core System: 7-pin housing accepts all BEST cores for quick, economical rekeying and master key system integration.
  • Professional Installation Features: 2 1/16" diameter chassis fits standard 2 1/8" door hole with multiple backset options including 2 3/4" standard, 3 3/4", and 5".
  • Corrosion-Resistant Components: Internal parts are brass or corrosion-treated steel with brass or bronze roses reinforced with steel liner for long-term reliability.
  • Optional Security Features: Available with breakaway feature to prevent overpowering by wrench, knurled knob option for accessibility applications, and security head machine screws.

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: Entrance
  • 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 door thickness from 1 3/8" to 2" and 2 1/8" bore hole for lock housing.
  2. Use manufacturer-provided templates to mark mounting hole locations accurately including 1" hole in door edge for latch housing.
  3. Prepare door by drilling required 2 1/8" diameter hole for chassis and 1" hole for latch tube per manufacturer specifications.
  4. Install chassis and latch assembly, selecting appropriate backset (2 3/4" standard, 3 3/4", or 5") and strike configuration for door thickness.
  5. Thread roses to chassis and adjust for proper door thickness, ensuring friction insert inside rose prevents loosening.
  6. Test knob operation, latch function, and key operation to verify proper installation and smooth operation throughout full range of motion. Refer to manufacturer documentation for complete installation details and troubleshooting.

Professional Applications

  • Government and Military Facilities
  • Commercial Office Buildings
  • Educational Institutions
  • Healthcare Facilities
  • Industrial and Manufacturing Plants
  • Multi-Tenant Residential Properties
  • High-Traffic Commercial Entrances

Why Choose BEST Quality?

BEST 8K Series knob locks deliver professional-grade reliability with solid brass or bronze construction machined from bar stock and Grade 1 performance that exceeds ANSI requirements. Internal components feature corrosion-resistant treatment and steel retractor with low friction bearings for smooth, wear-resistant operation over the long term. Engineered for demanding commercial applications where dependable security and durability 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:
Entrance
Door Hand Direction:
Non-Handed
Product Category:
Mechanical Locks
Department:
Door Hardware

BEST 8K37AB4ASTK626 – Frequently Asked Questions

1) Will the BEST 8K Series knob lock fit a 2-1/8 inch bored door prep?
Yes. The 8K chassis is 2-1/16 inches in diameter and drops into the standard 2-1/8 inch bore, with a 1 inch hole in the door edge for the latch tube. That is the same prep most commercial cylindrical locks already use, so on a door that has held a bored lockset before, the 8K goes back into the existing holes as long as the backset matches.
2) Which backset do I order for a BEST 8K knob lock, and does it cover a wide stile aluminum door?
Two backsets are orderable: 2-3/4 inches, which is the standard for commercial bored locks, and 5 inches for wide stile openings. The 2-3/4 inch is what you want on a typical hollow metal or wood door. Backset is the dimension from the door edge to the center of the bore, so measure the existing hole before ordering; a 2-3/8 inch residential prep is not one of the choices here.
3) Does the BEST 8K lock come with a core, or do I have to supply my own?
It ships less core. The 8K carries a 7-pin housing that accepts all BEST interchangeable cores, so you add the SFIC core keyed into your existing system. That is the point of the design for a facility already on BEST keying: the lock body goes on the door and your locksmith drops in a core that works on the master key system you already run. If you are not already on BEST cores, budget for cores plus a control key as a separate line.
4) Will the BEST 8K entrance knob latch into the strike that is already in my frame?
The 8K uses a 9/16 inch throw deadlocking latch. Two strike preps are orderable, an ANSI strike and a standard strike, so match the one already cut into your frame. An ANSI 4-7/8 inch frame prep takes the ANSI strike; a smaller full lip strike cutout takes the standard. Getting this wrong means filing the frame, so check the existing cutout rather than the door.
5) What is the closest Grade 1 heavy duty knob lock to the BEST 8K Series if I need a storeroom function instead of entrance?
The Sargent 8XG04 is a Grade 1 heavy duty single cylinder knob lock with a storeroom/closet function and a 2-3/4 inch backset, from the 8X Line Series. The BEST 8K Series is a Grade 1 heavy duty single cylinder knob lock in the entrance function, with 2-3/4 inch standard and 5 inch backsets available. Both are keyed cylindrical knob locks at the same ANSI grade, so the deciding factor is function: storeroom keeps the outside knob locked at all times, while entrance is the 8K's function.
6) I need a keyed Grade 1 knob lock for an office door but not the BEST core system. What else works?
The Corbin Russwin CK4851 is a Grade 1 entrance/office cylindrical knob lock with a Global knob and a conventional cylinder, covering doors 1-3/8 inch to 2 inch thick, from the 4000 Series. It differs from the BEST 8K Series in the cylinder: the 8K uses a 7-pin housing that accepts all BEST interchangeable cores, while the CK4851 takes a conventional cylinder. Choose based on whether the building is already on a BEST small format interchangeable core master key system.
7) What is the non-keyed equivalent for the corridor and closet doors when the entrance doors are getting BEST 8K knobs?
For openings that need no key, the Falcon X101 is a Grade 1 heavy duty cylindrical passage knobset with an interchangeable core, fire rated, covering doors 1-3/8 inch to 2-1/4 inch. The Schlage D10S is a Grade 1 heavy duty passage latch knob lock with an Orbit knob in the D Series, and the Corbin Russwin CK4310 is a Grade 1 passage/closet cylindrical lock with a Global knob for doors 1-3/8 inch to 2 inch. All three hold the same Grade 1 rating as the BEST 8K Series but are non-keyed, so they suit closets and corridors where the 8K entrance function is not needed.
8) Can I use a Grade 2 or Grade 3 knob lock instead of the BEST 8K on a high traffic commercial entrance?
Grade 2 and Grade 3 knob locks are built to a lower ANSI cycle and strength rating than the Grade 1 BEST 8K Series, which is specified as heavy duty commercial. Grade 2 keyed knob options include the Dexter C2000 entry/office ball knob lock for doors 1-3/8 inch to 1-3/4 inch and the Sargent 6G04 standard duty storeroom/closet knob lock. Grade 3 keyed options include the Cal-Royal BER00 entrance/office knob lock with a Kwikset keyway and the Master Lock BC01 biscuit knob keyed entry. These fit lighter traffic openings; where a specification calls for ANSI Grade 1, the 8K meets it and the Grade 2 and Grade 3 units do not.
9) My door is thicker than 1-3/4 inch. Which knob locks cover it besides the BEST 8K?
The BEST 8K Series adjusts for door thickness from 1-3/8 inch to 2 inch as standard, with special E trim for 2-1/8 inch to 3 inch doors. Among other commercial knob locks, the Falcon X101 Grade 1 passage knobset covers 1-3/8 inch to 2-1/4 inch, and both the Corbin Russwin CK4851 entrance/office and CK4310 passage locks cover 1-3/8 inch to 2 inch. Grade 2 and Grade 3 units such as the Dexter C2000 series, Pamex FTF Baron and Cal-Royal BER00 stop at 1-3/4 inch, so they will not make up a thicker door.
10) Do I need to know the handing before ordering a BEST 8K knob lock?
No. The 8K is non-handed, so one lock works on a left or right hand door and you do not have to survey the swing of every opening before you order. For a property manager stocking spares across a building, that means one part number covers every door in the group instead of a left and right split.
11) Should I use a Grade 1 knob like the BEST 8K or step down to a Grade 2 or 3 entrance lock?
Grade 1 is the top ANSI/BHMA cylindrical grade and is what belongs on high-traffic commercial entrances, corridors, and anything a facility opens hundreds of times a day. The 8K is heavy duty with knobs machined from solid brass or bronze bar stock and a steel retractor on low friction bearings. For lower-traffic doors where Grade 1 is more than the opening needs, ZenSupply carries Grade 2 entrance knobs like the Callan Edgewood and Grade 3 options like the Cal-Royal BER00. Where you need the same Grade 1 heavy duty class from another brand, the Sargent 8XG04 is a Grade 1 heavy duty knob lock, though in storeroom function rather than entrance.
12) What is the difference between the BEST 8K and the Falcon X101 for a job that needs interchangeable cores?
Both are Grade 1 heavy duty cylindrical knobsets built around an interchangeable core. The difference is function and door range: the 8K is an entrance function keyed lock adjusting 1-3/8 to 2 inches, while the Falcon X101 is a passage knobset, meaning it has no key at all and just retracts the latch. Use the X101 where the door only needs to latch, and the 8K where the door has to lock. The X101 carries a stated fire rating and covers 1-3/8 to 2-1/4 inch doors.
13) Can I get a knurled knob on the BEST 8K for a hazardous room, and what other options should I specify?
Yes, a knurled knob is available, which is the tactile warning surface used on doors into rooms that are dangerous to enter. Other options worth calling out on the order: a breakaway feature that stops someone overpowering the knob with a wrench, and security head machine screws. Knob shape is round or tulip, and roses come as 2-9/16 inch concave, 3-3/8 inch concave, 3-3/8 inch concave thick-door, or 3-3/8 inch convex. The inside rose snaps on with no exposed screws.
14) Is the BEST 8K single cylinder, and what does the entrance function actually do?
Single cylinder, keyed on the outside only. Entrance function means the outside knob can be locked and unlocked, and the key retracts the latch from outside; there is no exterior second cylinder and no thumbturn cylinder on the inside face. One security detail specific to BEST: the core has to be removed before a keyed knob can come off, which blocks a common attack on cylindrical locks.
15) I need a keyed entrance knob but my doors are 1-3/4 inch residential grade. Is the BEST 8K overkill?
For a light-use interior or residential opening it usually is. The 8K is a commercial Grade 1 heavy duty lock built around BEST interchangeable cores, which means core cost and a control key on top of the lock. For lower-duty keyed entry, ZenSupply carries the Kwikset 400P-CP Grade 3 keyed entry knob for 1-3/8 to 1-3/4 inch doors and the Pamex FTF Baron Grade 3 entrance/office knobset in the same thickness range. Step up to the 8K when the door is high traffic or has to sit on a master key system.
16) Is there a Grade 1 lever equivalent if my facility needs ADA-compliant hardware instead of knobs?
A knob is not an accessible operable part, so on doors that fall under accessibility requirements you want a lever rather than the 8K knob. Within Grade 1 cylindrical hardware ZenSupply carries the Schlage D Series, which is a Grade 1 heavy duty cylindrical line, and the Corbin Russwin 4000 Series in Grade 1. Keep the 8K for utility, mechanical, and back-of-house doors where a knob is still acceptable.
17) Is a dummy knob like the Schlage A170 a substitute for a BEST 8K knob lock?
No. The Schlage A170 is a single dummy trim, a Grade 2 non-keyed knob with no latch mechanism, and the same applies to the Cal-Royal BA40 dummy knob and the Omnia 442/00 single dummy latchset. They mount to a door face for pull purposes only. The BEST 8K Series is a keyed single cylinder entrance lock with a 9/16 inch throw deadlocking latch, so a dummy will not secure or even latch the opening.
18) What should I use for bathroom and bedroom doors in a building where the entrance doors use BEST 8K knobs?
Privacy function knobs suit those openings, since the BEST 8K Series is a keyed entrance function lock. The Dexter C2000 privacy ball knob lock is Grade 2 for doors 1-3/8 inch to 1-3/4 inch, the Cal-Royal BER20 is a Grade 3 privacy knob lock with brass trim for the same thickness range, and the Pamex FTF Baron privacy knob lock is Grade 3 for 1-3/8 inch to 1-3/4 inch. Privacy knobs lock from inside with no key cylinder, which is what a restroom or bedroom door needs.
19) Is a Kwikset 400P Polo entry knob the same thing as a BEST 8K entrance knob lock?
They share the entrance function but not the build. The Kwikset 400P-CP keyed entry knob is Grade 3 for doors 1-3/8 inch to 1-3/4 inch and ships with a round corner adjustable latch and round corner strike. The BEST 8K Series is Grade 1 heavy duty commercial with knobs machined from solid brass or bronze bar stock, adjustable 1-3/8 inch to 2 inch, and a choice of ANSI or standard strike. For a commercial opening written to Grade 1, the Kwikset does not carry that rating.
20) For a classroom door, is the Dexter C2000 classroom knob an alternative to the BEST 8K?
The Dexter C2000 classroom cylindrical ball knob lock is Grade 2, keyed, non-clutching, for doors 1-3/8 inch to 1-3/4 inch, and its classroom function is keyed from outside to lock and unlock the outside knob. The BEST 8K Series is a Grade 1 entrance function lock. If the school specification calls for a classroom function, the C2000 provides it; if it calls for Grade 1, the 8K is the one that meets the rating.
21) Can I put a BEST 8K knob on a door that already has an exit device?
No, an exit device needs trim built for it. The Sargent 28C-KNOB is exit device trim with a knob and rose in an entrance function for 1-3/4 inch doors, and the Imperial USA ED-BKL580 is knob trim in a storeroom function for the ED-500 Series. The BEST 8K Series is a bored cylindrical lock that mounts through a 2-1/8 inch door hole with a 1 inch latch bore, which is a different door prep entirely.
22) I need a keyless knob lock for a back door instead of a keyed BEST 8K. What is available?
The Lockey 3830 is a mechanical keyless combination knob lock with an auto-locking passage function for doors 1 3/16 inch to 2 inch. It is operated by a pushbutton code rather than a key, so no cores or keys are issued. The BEST 8K Series is a keyed single cylinder lock on a 7-pin BEST core housing, which is the choice when the door has to sit inside a master key system.
23) What finish options does the BEST 8K knob lock come in for matching the rest of a building?
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. 626 satin chrome is the usual commercial standard, and the 626AM antimicrobial version is the one to specify for healthcare and food service where touch surfaces matter.
24) How much clearance does a BEST 8K knob need off the face of the door?
The knob is 2-1/8 inches in diameter with a 2-7/8 inch projection from the door face. That matters where a door swings back against a wall, sits next to a return wall, or where a stop has to be set so the knob does not punch the drywall. Check that 2-7/8 inches before committing on a tight vestibule or a door in a corner.
25) Will the BEST 8K corrode in an exterior or wash-down location?
Internal parts are brass or corrosion-treated steel, and the roses are brass or bronze reinforced with a steel liner. That is the construction you want for a humid corridor, a mechanical room, or a coastal exterior door where plated pot metal internals give out first. The finish choice matters too on exposed openings.
26) What is a fire rated knob lock option if the opening is a rated door?
The Falcon X101 Grade 1 heavy duty passage knobset and the Falcon W101 Grade 2 medium duty passage/closet knob lock with a 2-3/4 inch backset both carry a fire rating. Both are passage function, so they suit rated corridor and closet doors rather than keyed entrances. Confirm the rating on the specific opening against the door and frame label before ordering.
27) Are decorative brass knobs like the Emtek or Baldwin sets an alternative to a commercial BEST 8K knob lock?
They serve a different opening. The Emtek Classic Brass Crystal Georgetown and Providence knobsets and the Emtek Arts and Crafts Hammered Egg knobset are dummy function pairs, and the Baldwin Estate 5011 Colonial and Estate 5000 Baltimore knobs are passage and privacy functions with a 2-3/8 inch backset on the 5000. The BEST 8K Series is a keyed Grade 1 commercial entrance lock with 2-3/4 inch and 5 inch backsets. The decorative sets are residential trim choices, not keyed commercial security.
28) Which knob locks besides the BEST 8K are non-handed so I do not have to specify swing?
The BEST 8K Series is non-handed, so a single part number covers left and right hand doors. Among peers, the Arrow MK01 and RK01 Grade 2 passage knob locks, the Dexter C2000 passage and privacy ball knob locks and the Corbin Russwin CK4410 Grade 2 passage/closet lock are all non-keyed passage or privacy units where handing is not a factor either. For keyed openings the 8K is the non-handed Grade 1 choice.
How fast can I get the BEST 8K37AB4ASTK626 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 8K37AB4ASTK626 come with a warranty?
Absolutely. The BEST 8K37AB4ASTK626 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 8K37AB4ASTK626?
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 8K37AB4ASTK626 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.
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