Thermwell 15"x24" Heat & AC Deflector for Baseboard Register. Made of heavy-duty plastic with an insulation R-value of 0, it measures 4.9" in height, 2.75" in depth, and 15" in width. This deflector is designed for use with central forced air heating and cooling systems and can be easily installed by magnetic hold on baseboards up to 25 inches long. It effectively redirects heat for better heating in winter and directs air conditioned air up for improved cooling in summer. Comes in a pack of 12.