XRAY X4 Split Rear Graphite Upper Deck. This optional rear upper deck is designed specifically for asphalt tracks. The top deck features milled holes for special tweak-free top deck screws. Being two pieces, this will allow for more flex options and can easily be adjusted between the front and rear. Package includes one rear upper deck.
Only one rear screw is used. This allows maximum flex and provides maximum steering. However, the car is less stable on-power
Both screws are used. This setting gives reduced flex both in front and rear. Mid-corner steering is decreased, rotation is decreased. This setting provides maximum stability and makes the car easier to drive.