This is an Xray Xb2 Slipper Eliminator. When using this you can eliminate all of your heavy slipper components and free up some horsepower! Especially in stock racing this has made a noticeable difference. After all, the input shaft is turning the most rpm out of any transmission component. To install this eliminator all you will need is 3 3x6mm screws and 1 kimbrough style spur gear. This has been a proven product and has so far been the lightest product on the market.