The Design House 727438 Deadbolt locks and unlocks with a key on one side and a twist knob on the other. 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). This deadbolt is commonly used on front doors and back doors. Use this knob on standard 1-3/8-inch and 1-3/4-inch thick doors with a cross bore 2-1/8 in dia or edge bore 1-1/16 in dia. (1 in. x 2-1/4 in. radius corner faceplate). This product is ANSI Grade-3 certified, which means this deadbolt is rated for residential security. Designed and manufactured by Design House, the trusted source for quality lighting, hardware, plumbing, kitchen, and bath products for every taste and budget.