The TTS Gold is a single element device - 120 volts, 35 watts - ideally suited to heavily-muscled areas of the back. All Thermotex Infrared Heating Pad systems come with covers featuring adjustable Velcro fasteners and are machine washable. Face covers are 100% nylon and back covers consist of a 50/50 nylon-cotton blend. All systems come with hi-low power settings. On the low setting, after full heat up, the micron range holds steady at 9.1376 based on surface temperatures of 111F. On the high setting, the micron range is 9.1089 to 8.7778 based on the range of surface temperatures of 113F to 135F. The infrared elements themselves are not flexible and should never be bent.