Kwikset Halo Wi-Fi Enabled Smart Lock, Design: Contemporary, Power Source: Battery, Backset Type: Adjustable, Backset Size: 2-3/8, 2-3/4 in, Door Thickness: 1-3/8 to 1-3/4 in, Number of Cylinders: 1, Key Type: Keyed, Re-Key Technology: SmartKey, Latch Type: Adjustable Round Corner, Faceplate Size: 1 x 2-1/4 in, Strike Type: Round Corner, Strike Size: 2-3/4 x 1-1/8 in, Number of User Codes: 50, Commercial/Residential: Residential, Center to Center: 5-1/2 in, Projection Size: 2-1/2 in, Operating System Compatibility: Android, Brass/Steel, Matte Black, Dimensions: 2-5/32 in L x 3-9/16 in H, Includes: (4) AA Batteries