HTGSupply Floating Seed Starter Germination Kit with Tall Humidity Dome, Root Plugs & Heat Mat Electrical (heat mat): 17 watts, approx 0.14 amps @ 120v Includes: watertight tray, large 7" humidity dome, heat mat, 55-cell floating insert, (55) all natural root plugs Dome features 2 adjustable vents for humidity control Measures 21.25" long ; 11" wide ; 10" high (assembled)