The Design House 782771 Double Cylinder 2-Way Latch Deadbolt requires a key to open the deadbolt from both inside and outside your house. Finished in polished brass and designed for left or right hand doors, this deadbolt fits the two most common backsets in the U.S. (2-3/4-inch and 2-3/8-inch). The 1-inch latch bolt is plated in nickel and features a 5-pin high security core. Once in place, the bolt does not budge. Use this deadbolt on standard 1-3/8-inch and 1-3/4-inch thick doors. This product has a 1-inch by 2-1/4-inch radius corner face plate. If you are preparing your door for this deadbolt, the cross bore should be 2-1/8-inches in diameter and the edge bore should be 1-inch in diameter. This product is ANSI Grade-3 certified, which means this deadbolt is rated for residential security.