6400LN Series Monolock Yale 6400LN Monolock Yale 6400LN Monolock Based on the design of Yale's robust cylindrical locksets, the 6400LN Monolock continues the tradition of quality and dependability as a preassembled lock series designed to retrofit Yale Monolock as well as Corbin Russwin Unit Lock and Falcon® Retrofit Lock installations. UL-cUL: UL-cUL fire-rated up to 1-1/2 hours Mechanism: Heavy-gauge steel, zinc-plated, dichromated Backset: 2-3/4" Latchbolt: 1/2" stainless steel throw Guardbolt: Deadlocks latchbolt when door is closed; standard on all locking functions Door Thickness: 1-3/4" only Lead Shielding: Available to order Cylinders: Brass, 6-pin, keyed-random cylinder with two keys furnished standard, 7-pin available to order. Reversibility: Handing must be specified for all functions and designs Strikes: 1-1/4" lip ANSI strike supplied; other lip lengths and strikes available to order; all reversible Finishes: Available in 626 finish only Warranty: 7-year mechanical Downloads Catalog Installation Instructions Templates Close Want to learn more? Complete the form below to get the conversation started. loading 5400LN Series Lever Locks 5300LN Series Lever Locks 4700LN Series Lever Locks