Waste Gas Interface EVC631 For use with our EVC3000 evacuation system or any fan style system. This is a must-have device if you have an active fan scavenger system. Using a fan to remove waste gases creates negative pressure within the anesthesia system which can pull fresh anesthetic gas away from the subject before they can reach an appropriate plane of anesthesia. The interface unit balances the pressure between the anesthesia machine and the active evacuation unit, keeping your subjects safe and ensuring a level plane of anesthesia. REAR VIEW SIDE VIEW Dual inlets for induction chamber and breathing circuit. Includes 20 ft. of 22mm clear EVAC hose and 4 ft. of 19mm blue EVAC hose. Includes reservoir bag Mounting hardware for all 2-in. posts available