Bypass Dampers Think Young! Bypass Layout Electronic Bypass Dampers Best Choice Built In Static Pressure Controller 0.17 and 5 W.C Low Leak Blade Seals / Oval Blade Easy to Install and Adjust Pre-wired at the factory, Tube and Probe Included LED shows blade moving Built in Time Delay prevents hunting Finer Control 4092/3092 Barometric Bypass Dampers 4095/3095Weighted Arm Dampers High Quality Pressure Relief Dampers The choice of majority of zoning manufacturers Static pressures up to 1inwc 8 to 16 Round Multiple Rectangular Sizes up to 20 x 12 Think Young!