The WS4949 2-button wireless key adds wireless convenience and value to any DSC security system by providing users with a competitively priced wireless solution that includes a number of features and benefits. The WS4949 provides users with a sense of control over their security system and the added confidence that comes with portable personal protection within the home. Compact and user-friendly, the WS4949 features two scratch-resistant buttons that when activated perform either arming or disarming functions. When the two buttons are pressed simultaneously the panic function is activated. *False Alarm Prevention: By default, the key includes a panic button. It will require the user to press and hold for approximately 3 seconds. This was designed to reduce the possibility of a false alarm. Features: 2-button, 3-channel wireless key Activation via 2 large, scratch resistant buttons Full 3-second delay on panic function Integrated LED to indicate signal transmission Reliable 433 MHz technology Long-life lithium batteries included Water resistant Approval Listings: Not CE Listed, FCC/IC Compatibility: MAXSYS® Wireless Receiver PC4164-433 PowerSeries Wireless Receiver Zone Expansion Module PC5132-433 Wireless Receiver RF5108-433 Fixed-Message LCD Keypad with Integrated Wireless Receiver RF5501-433 Envoy LCD Self-Contained Wireless Security System NT9005 Specifications: Dimensions: 2 1/4 x1 1/4 x 7/16 (57 mm x 32 mm x 13 mm) Weight: 0.6 oz (18 g) Operating Environment: 32º to 120ºF (0º to 49º C) Relative Humidity: 5% to 93%