Installs quickly with removable wing knob. 24/7 security monitoring. Remote open from anywhere. Real-time reminders. Wi-Fi connectivity. Loud, audible and visual alerts from device. Back up key access. Sealed compartment to control moisture. Exterior dimensions (wings retracted): 6" x 12.8" x 3.4". Exterior dimensions (wings extended): 6" x 22.6" x 3.4". Interior dimensions: 4.6" x 8.4" x 2.5". Weight with batteries installed: 4.15 lbs. Smart phone app available for IOS and Android systems. Requires (4) AA batteries (not included). Boxed.