Rollerbolt operated by push or pull from either side. Deadbolt operated by key from either side using a double cylinder (not supplied) or by key outside and thumb turn inside using a cylinder with turn(not supplied). Pierced to accept 20mm and 38mm centre bolt through fixing escutcheons. Rollerbolt is brass and adjustable to suit either hand. Deadbolt is also brass with two hardened steel rollers and the throw is 14mm. The measurements are as follows: 76mm(A) lock comes with 57mm(B) backset, 101mm(A) lock comes with 82mm(B) backset