This Four-Outlet Thermostat works with Redi-Heat™ Propagation Mats to help maintain the correct soil temperature for germination. Features a 52"L sensor cable, built-in 15A fuse and 6'L power cord. Four 120V outlets allow you to plug in multiple propagation mats (up to 1,800 watts total). Propagation mats sold separately: 5'L x 12"W (Item #227572, 150 watts), 10'L x 12"W (Item #227573, 300 watts), 20'L x 12"W (Item #227574, 600 watts), 5'L x 21"W (Item #227575, 150 watts) or 10'L x 21"W (Item #227576, 300 watts).