 Designed to add keyless access and audit trail capability anywhere with a glass door  Vandal-resistant, made from strong alloy metals  Weatherproof from (-31? to ??151?F)  Operates on two long lasting lithium 3V batteries  Push-button locks are fingertip programmable and can be scheduled to automatically lock and unlock during designated hours  Each model comes with a 1-1/4〃 key override mortise cylinder