Mace Security MAS-WA-CON MaceAlert SOLO Multi-Surface Contact Sensor System Expansion Accessory Wireless monitoring of garage doors and difficult multi-surface window and door frames Magnetic sensor contacts can be surface-mounted independently from attached transmitter Status LED for window/door open sensing and low battery warning Includes (1) sensor with installation adhesive strips, anchors, screws, and product manual, requires (2) AAA alkaline batteries not included Mace Security 12-month limited product warranty with USA-based, toll-free telephone technical support