Corbin Russwin DL4113 Single Cylinder Mortise Deadlock

When a door needs a deadbolt that a keyholder controls from outside but an occupant can operate freely from inside, the single cylinder mortise deadlock is the right hardware. The Corbin Russwin DL4113 is exactly that. It's part of the DL4100 Series, a Grade 1 mortise deadlock with key operation from the outside and thumbturn operation from the inside, UL listed for fire door applications, non-handed, and built with a heavy wrought steel case and a steel deadbolt with a hardened anti-cut pin. It's the standard specification for stairwells, utility rooms, exterior secondary doors, and institutional spaces across schools, hospitals, government buildings, and commercial facilities.

This is also the direct replacement for the older Corbin Russwin DL4013 Series, which was produced during the Emhart period before DormaKaba's acquisition. If you're replacing a DL4013 on an existing door prep, the DL4113 installs without modification. For the full range of commercial mortise locks across every brand, or to view compatible Corbin Russwin ML2000 Series mortise locks, browse our catalog.

How the DL4113 Single Cylinder Function Works

Outside the door, a key in the cylinder extends or retracts the 1" deadbolt. Inside, the thumbturn handles the same operation without a key. The inside thumbturn is always operational. There's no push button, no indicator, and no way to accidentally lock someone inside without a key to get out. The single cylinder design makes this the appropriate specification for fire egress doors and any AHJ jurisdiction requiring free inside egress from a deadlocked opening. If double cylinder operation is required (key from both sides), that's the DL4114. If an occupied/vacant indicator is needed on the inside, the DL4116 adds that function.

Corbin Russwin DL4113 Technical Specifications

Series: DL4100, ANSI No. E6070. Grade: ANSI/BHMA Grade 1. Function: single cylinder, key outside, thumbturn inside. UL Listed: yes, for use on fire doors. Handing: non-handed. Door thickness: standard 1-3/4" (44mm); optional thicknesses available via Quick Codes. Backset: standard 2-3/4" (70mm); optional 2-3/8" (60mm). Lock case: heavy wrought steel with zinc dichromate finish for corrosion resistance. Front: brass, bronze, or stainless steel, 4-5/8" (117mm) x 1-1/8" (29mm). Bevel adjustment: 1/8" (3mm) in 2" (51mm), fits flat and beveled doors. Deadbolt: steel with hardened anti-cut pin, 1" (25mm) throw. Strike standard: wrought brass or bronze, 3-1/2" (89mm) x 1-1/8" (29mm); optional strikes available. Cylinder: 6-pin, L4 keyway, keyed random; other keyways available from stock. Keys: two nickel silver standard. Warranty: one-year limited.

Deadbolt Construction: Why the Hardened Pin Matters

The DL4113's deadbolt is steel with a hardened steel anti-cut pin running through the bolt face. That pin is what prevents the deadbolt from being cut with a hacksaw once extended into the strike. On a mortise deadlock used in an institutional or commercial application, this is a standard requirement. A bolt without the hardened pin can be compromised with basic hand tools in seconds. The hardened pin adds meaningful resistance without any operational change to how the lock functions day to day.

Available Keying Options

The DL4113 ships with an L4 keyway as standard, but Corbin Russwin offers a full range of keyways from stock for facilities running existing master key systems. Available keying configurations include keyed random, master keyed, construction master keyed, seven-pin (FC) conventional, and interchangeable core in both small format and large format (LFIC and SFIC). For IC core options and compatible cylinders, browse our cylinders, cores, and keys catalog.

Where the DL4113 Gets Specified

Stairwell doors, exterior secondary entry doors, utility and mechanical rooms, rooftop access doors, institutional corridor deadlocking applications, and any commercial or institutional opening where a UL fire listed Grade 1 mortise deadlock is required by code or specification. The non-handed design covers both door swings from a single SKU, simplifying procurement across large door schedules with mixed handling.