Latchbolt operated by lever handle from either side. Deadbolt operated by key from either side. 76mm and 101mm sizes are pierced to accept 38mm centre horizontally and 38mm centre diagonally opposed bolt through fixing furniture; 63mm size pierced diagonally only. Latchbolt is brass and reversible; projection is 12mm. Deadbolt is also brass with two hardened steel rollers and the throw is 16mm. The measurements are as follows: 63mm(A) lock come with 45mm(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. 200 standard differs numbered 001-200. If you are choosing the master keyed lock then these are available in master, sub and grand master keyed