Corbin Russwin 574F25-8 CK4400...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$44.30
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Corbin Russwin 574F25-8 CK4400 Series Cylindrical Lockset Backset Extender Kit, Extender Only for 2-3/8" Latch Unit

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Model: 574F25-8

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

$44.30
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Corbin Russwin 574F25-8 CK4400 Series Cylindrical Lockset Backset Extender Kit

The Corbin Russwin 574F25-8 is a purpose-built Backset Extender Kit for the CK4400 Series Cylindrical Lockset, designed specifically as an Extender Only component that must be paired with a compatible 2-3/8" Latch Unit to complete the assembly. This commercial-grade replacement part allows installers to adapt the backset configuration of existing CK4400 Series locksets, making it an essential accessory for service, renovation, or upgrade projects in demanding commercial environments.

Key Features

  • CK4400 Series Compatibility: Engineered exclusively for use with the Corbin Russwin CK4400 Series Cylindrical Lockset, ensuring precise fit and proper function within the established hardware family.
  • Backset Extension Capability: Extends the backset of the existing latch assembly, enabling adaptation to specific door preparations and hardware configurations that require a longer backset.
  • Required Pairing with 2-3/8" Latch Unit: This Extender Only component must be added to a compatible 2-3/8" Latch Unit, it does not include the latch unit itself, allowing targeted replacement of only the extender component.
  • Commercial-Grade Quality: Manufactured to Corbin Russwin's commercial standards, providing the durability and reliability expected in high-traffic institutional and commercial applications.
  • Replacement Parts Classification: Categorized as a certified replacement part within the CK4400 Series, ensuring form, fit, and function match original equipment specifications.
  • Targeted Component Replacement: Allows service technicians and facility managers to replace only the extender component rather than the entire lockset assembly, reducing downtime and overall maintenance costs.

Technical Specifications

  • Department: Door Hardware
  • Product Category: Mechanical Locks
  • Product Group: Parts and Accessories
  • Subcategory: Parts and Accessories
  • Product Subgroup: Parts and Accessories
  • Product Type: Latches
  • Parts and Accessories Type: Replacement Parts
  • Commercial/Residential: Commercial
  • Product Model: 574F25-8
  • Features: Corbin Russwin Lock Parts

Typical Applications

  • Commercial Office Buildings Requiring Lockset Servicing
  • Educational Facilities Maintaining Existing CK4400 Series Hardware
  • Healthcare Institutions with Established Cylindrical Lockset Installations
  • Government and Municipal Buildings Undergoing Hardware Renovation
  • Retail and Hospitality Establishments Servicing Existing Door Hardware
  • Industrial and Warehouse Facilities Performing Scheduled Maintenance
  • Multi-Tenant Residential Properties with Commercial-Grade Door Hardware

Why Corbin Russwin CK4400?

Corbin Russwin CK4400 Series components are manufactured to rigorous commercial standards, delivering the precision fit and long-term performance that facility managers and security professionals rely upon. The 574F25-8 Backset Extender Kit reflects Corbin Russwin's commitment to serviceability, providing targeted replacement parts that preserve the integrity of the original lockset assembly without requiring full hardware replacement.

Manufacturer Resources

Product Specs

Department:
Door Hardware
Product Category:
Mechanical Locks
Product Group:
Parts and Accessories
Subcategory:
Parts and Accessories
Product Subgroup:
Parts and Accessories
Product Type:
Latches
Parts and Accessories Type:
Replacement Parts
Commercial/Residential:
Commercial
Product Model:
574F25-8
Features:
Corbin Russwin Lock Parts

Corbin Russwin 574F25-8 – Frequently Asked Questions

1) Does the Corbin Russwin 574F25-8 backset extender come with a latch unit?
No. The 574F25-8 is the extender only. It has to be added to a compatible 2-3/8 inch latch unit, which is ordered separately. If your door is bored for a 2-3/8 inch backset and you are servicing the whole latch, you will need both pieces on the truck.
2) Will a Corbin Russwin 574F25-8 extender fit any cylindrical lockset?
No. It is built for the Corbin Russwin CK4400 Series cylindrical lockset and nothing else. If the lock on the door is another Corbin Russwin series or another brand, this part will not adapt it.
3) What does a backset extender kit actually do on a CK4400 lockset?
It extends the backset of the existing latch assembly, so a 2-3/8 inch latch unit can be adapted to a door prep that needs a longer backset. On commercial doors the two standard backsets are 2-3/8 and 2-3/4 inches, and the extender is how you cover the longer prep without swapping the entire lockset.
4) My CK4400 doors are already prepped 2-3/4 inch. Do I order the extender or a 2-3/4 latch?
The extender route starts with a 2-3/8 inch latch unit, since the 574F25-8 is designed to be added to that latch to reach the longer backset. If you would rather not stock two pieces per opening, order a latch unit made for the longer backset directly. Buying the extender without the matching 2-3/8 inch latch leaves you with half an assembly.
5) Is there a latch that handles a 2-3/4 inch backset on its own instead of adding an extender to a 2-3/8 inch unit?
Yes. The Corbin Russwin 574F25-8 is an extender-only part that must be paired with a compatible 2-3/8 inch latch unit to reach the longer backset, and it is built specifically for the CK4400 Series cylindrical lockset. If you are not tied to CK4400 trim, the Deltana DLP23875 is a drive-in latch with an adjustable backset of 2-3/8 inch or 2-3/4 inch in a single unit, in a passage/privacy function, for doors 1-3/8 inch to 2 inch thick. The Deltana is a complete latch rather than an add-on component, so it replaces the latch entirely rather than adapting an existing one.
6) Will a Kwikset 84290 plain latch work as a substitute for the Corbin Russwin 574F25-8?
No, they solve different problems. The Kwikset 84290 is a square corner plain latch at a fixed 2-3/8 inch backset, so it is a whole latch for a 2-3/8 inch prep and offers no way to reach a longer backset. The Corbin Russwin 574F25-8 is not a latch at all: it is a backset extender that mounts to a compatible 2-3/8 inch latch unit within the CK4400 Series cylindrical lockset family to extend the backset. If your door is prepped at 2-3/8 inch and you simply need a replacement latch, the Kwikset is the type of part you want; if your CK4400 lockset has to reach a deeper backset, the extender is the part that does it.
7) Can I use the 574F25-8 instead of replacing a whole CK4400 lockset?
That is the point of it. The 574F25-8 is a Corbin Russwin replacement part, so a service tech swaps the extender component alone and leaves the rest of the lockset in the door. For a facility standardized on CK4400 hardware, that keeps the opening in service and the keying untouched.
8) Is the Corbin Russwin 574F25-8 suitable for residential doors?
It is a commercial part. The CK4400 Series it belongs to is commercial cylindrical lock hardware used in offices, schools, healthcare and multi-tenant buildings. On a residential door with a common tubular lock, a drive-in latch with an adjustable backset is the usual route instead, for example the Deltana DLP23875 for passage and privacy or the DLE23875 for entry, both of which cover 2-3/8 and 2-3/4 backsets on doors 1-3/8 to 2 inches thick.
9) I need a fire-rated latch for a labeled opening - does the Corbin Russwin 574F25-8 cover that?
The 574F25-8 is a backset extender kit for the CK4400 Series cylindrical lockset and is supplied as an extender component only, so the latch unit it attaches to governs the opening. Among comparable latches, the Kwikset 83521 is a RCAL plain latch carrying a UL 3 hour rating for BBL, KNL, CNL and PLL trim, and the Kwikset 83518 is a RCAL adjustable square drive latch also carrying a UL 3 hour rating. Those are complete latch units for Kwikset cylindrical hardware, not accessories for a Corbin Russwin lockset.
10) What other lockset service parts are sold on their own like this extender is?
The Corbin Russwin 574F25-8 is one of several parts sold as a single serviceable component rather than a full assembly. It is a CK4400 Series backset extender supplied without the latch unit, classified as a replacement part for commercial door hardware. Comparable single-component parts include the Emtek 83228, which is a faceplate and screws set for a tubular pocket door privacy latch with square corners, and the Emtek LC9-DBLTCH motorized deadbolt latch from the EMPowered series. Each addresses a different piece of the assembly, so match the part to the component you are actually replacing.
How fast can I get the Corbin Russwin 574F25-8 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 Corbin Russwin 574F25-8 come with a warranty?
Absolutely. The Corbin Russwin 574F25-8 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 Corbin Russwin 574F25-8?
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
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