Standard Features - Large, Clear Backlit Digital Display Easy-to-read in various lighting conditions. (Also available in smaller standard screen size) - Precise Comfort Control - Maintains consistent comfort to the highlest level of accuracy - Wireless Can be placed anywhere in the home without running wires or cutting into your walls - Easy-Access Battery Replacement Flip-out door allows for easy battery replacement without removing or disassembling the thermostat - Built-in Instructions Simple, pull-out instruction manual - Model Numbers TH6220D1002, TH6110D1005, TH6320D1004, TH6110D1021, TH6220D1028 - 5-Year Warranty