These Seedling Heat Mats are Re-engineered for better performance and greater durability! The new, stronger heating wire, and thicker multi-layer construction offer more uniform heating and the durability to withstand rugged greenhouse environments. Increases success of seedlings and cuttings. Warms root area 10-20˚F over ambient temperature to improve germination. Light, watering and planting information on mat. Waterproof construction. 6 foot power cord. The only UL Listed seedling heat mats on the market!. 50% thicker construction.