This heavy duty storeroom door lock is made from cylindrical, steel coated with zinc dichromate (corrosion resistance) construction and complies with ANSI A156.2, series 4000, grade 2, (400,000 cycles), UL listed for 3 hour fire door. It features a 6 or 7 pin SCC keyway with two nickel keys per lock, door range: 1 3/8" to 1 3/4"; backset: 2 3/4" standard; and strike: T strike (1 1/8" x 2 3/4") standard.