Paddle valve switch with 1/4" barb fittings, just run one line from your air tank and the other line to your bags. You can mount these anywhere, they are easily snapped in or push in two tabs to remove.No electrical hookup needed. Save tons of money by not having to buy solenoids. 2 of these needed for a front/back system or 4 for a 4 path. Each Paddle does up and down Check other auctions for mounting panels with these paddles installed with a gauge. These will take a full size car from all the way down to all the way up in less then 10 seconds.