Latchbolt operated by lever handle from either side. Deadbolt operated by key from either side. 63mm and 76mm cases are hardened steel and are pierced to accept 38mm centre horizontally opposed bolt through fixing furniture. Latchbolt is brass and reversible; projection is 12mm. Deadbolt is also brass with two hardened steel rollers and the throw is 20mm. The measurements are as follows: 63mm(A) lock come with (B) backset and 57mm(C) centres, 76mm(A) lock comes with 57mm(B) backset and 57mm(C) centres, 101mm(A) lock comes with 82mm(B) backset and 57mm(C) centres. 1000 differs unnumbered