Broan HRV70SE Heat Recovery Ventilator, 120V Side Ports for 4" Ducts - 73 CFM Delivers 35 to 73 CFM of balanced ventilation The compact, lightweight size of 30 lbs. allows you to install the unit without having to open it Integrated pressure taps and balancing dampers quickly measure and balance air-flow Integrated hooks and port straps allow for a faster and easier installation Removable terminal block allows for quicker wall control connections ENERGY STAR Qualified