Super Sprouter? 4 Tray Seedling Heat Mat is designed for 4 standard 10 in x 20 in propagation trays placed side by side. The heavy duty construction makes this mat very durable and allows even warming throughout the trays. The Super Sprouter? 4 Tray Seedling Heat Mat warms the rooting area approximately 10?F – 20?F over ambient temperatures to improve the germination process. In doing this, it helps the gardener have a better success rate with seedlings and cuttings. More consistent heating with fewer hot spots than other seedling heat mats on the market. Ed Hume seal of approval. 110 Watts. 5 ft 120 Volt power cord. Dimensions: 21 in x 48 in.