This adjustable baseboard register air deflector redirects and channels airflow as it leaves a heating/cooling vent for added comfort, saving energy. Very strong metal magnets are attached to the air deflector for instant mounting on your heating/cooling register. The clear deflector adjusts from 15 inches to 25 inches wide, is 4-1/2 inches high, and 3-1/4 inches deep. The deflector is made of clear polycarbonate with a melting temperature of approximately 325 degrees Fahrenheit . It should only be used with registers for central forced air heating and air conditioning.