There might be a small infestation problem in the air ducts. Vent Dragons are designed to hang on your wall. It does not need to be installed in an actual heater duct. Vent Dragons comes with a little remote control to light up the eyes of the two little monsters and surprise your guests and friends. The lights are powered by 3 AA batteries and should burn for 150 hours before you need to replace them. To replace the batteries unscrew the grate and lift off, the batteries are in a small pack inside. The lighted eyes have 8 different settings from fast blinking to continually glowing and there is a timer to turn them off in 6 hours. Enjoy!