It takes some height above the tank to route the hose, and a canister far enough from the heat to allow the vapors to condense for them to run back to the tank. This is ideal, but seldom achieved...and it is nearly impossible with the short length of the Spyder emissions system (except 2014 RT) and the heat from the exhaust and lack of venting/air movement that drives off more fumes than the system can handle.