This New York style back plate is designed for the interior side of a bedroom or bathroom door. It features a classic crescent thumb to activate the privacy mortise lock from inside the room. Made of solid, wrought brass in 4 finishes.Dimensions: 7" H x 2 1/4" W. Inside collar diameter: 5/8". Center to center spacing of keyhole to knob collar: 2 1/4". Thumbturn spindle: 3/16" x 1 5/8"; oriented on the diamond.