This mat measures 3 inches wide and 18 inches long, with a 5 1/2-floot cord that plugs into any household outlet. When plugged in, it delivers 9 watts (120 volts) of heat, but never gets warm enough to present a burn hazard or damage the paint or finish on your windowsill. At season's end, just roll it up and store for next winter!
Using a heat mat enables you to keep the room economically chilly while still providing enough heat to germinate seeds and grow on young seedlings. If you are using a domed seed starter, just keep the dome on, which will create a warmer air temperature for the seeds and seedlings. If you are beginning seeds in a tray or other structure and your room temperature is lower than needed for germination, just cover with plastic wrap until the seeds sprout. The Windowsill Heat Mat makes all the difference! Great for potted plants that need a bit warmer winter soil, too!