The Westhold G3 Pouch allows you to mount your rechargeable transponder to the frame of your car in an upright position. It is most appropriate for G3 transponders (G3 CAR, G3 KART, and G3 MX), Activated-CAR transponders (green), and Activated-KART transponders (blue). Large grommet holes allow you to zip-tie the (Zip ties not included) case to the underside of the car. There is a clear plastic window where the indicator lights can be seen.