General description Seedling Heat Mat is perfect for seasoned growers, beginners, and kids. It improves germination by warming the root zone 10-20°F (5-10°C) above ambient temperature. Bottom heat is one of the most important and effective ways to improve germination and rooting. Seedling heat mats have been redesigned with a thermostat controller for better performance and longer life! Technical specifications Dimensions: 50.8 cm x 50.8 cm Temperature increase: 10-20°F (5-10°C) above ambient temperature