Single cylinder deadbolt (thumb turn inside) is best used for exterior locking applications This deadbolt lock offers ANSI Grade 3 performance for exterior locking applications Aged bronze finish provides a sleek appearance Deadbolt is four-way adjustable for 2-3/8 in. (60 mm) or 2-3/4 in. (70 mm) backset, square, or rounded corners Includes one single cylinder deadbolt