Increase your success with seed germination, seedlings and cuttings by warming the root area up to 10-20°F over the ambient temperature using heat mats. Available in sizes to accommodate one, two or four planting flats. Light, watering and planting information printed on mat. Waterproof construction, 6' power cord, UL listed. The Two Flat Size Mat is 20 x 20. Check out the One Flat and the Four Flat sizes as well.