Battery Type: 3 Volt Lithium; Duracell DL123A, Panasonic CR123A. Battery Life: 12 Months Minimum Battery Replacement: Upon Low battery report and/or during annual maintenance. Operating Temperature Range: 32F to +145F. Operating Humidity Range 0 to 85% RH. Testing: Follow this manual and NFPA 72 or local requirements. Transmission: In compliance with FCC part 15 for reception on equipment manufactured by Tyco Fire & Security GmbH Test Transmission: Every 90 seconds. Low Battery: 2.70 volts nominal Compatibility: Refer to the CWSI control panel manual. Size: 4.75 Inches high, 2.55 Inches wide, 1.58 Inches deep. Weight 6.4 oz. Standby Current: 33.8 ua. Alarm Current: 30ma. Initiating loop rating: 3 Vdc, 1ma.