Complies with ANSI A156.2, Grade 2 (400,000 cycles) lever, UL listed for 3 hr fire door. Door range of 1-3/8 to 2 in. Backset of 2-3/4 in standard. Strike, T-strike (1-1/8 in x 2-3/4 in). Cylindrical, steel-coated with zinc dichromate (corrosion resistance). Latch bolt is operated by a lever from either side, outside lever is locked by turn button from inside, it is unlocked by a key from outside or rotating inside lever. There is a six-pin SCC keyway with two nickel keys per lock.