Recommended for use on carpet and tracks with a high traction, the automobile rotates better and drives better through corners. Fits both XB4 & XB4 2WD. Aluminum back paid off suspension system holders with included Suspension Settings (I.S.S.) permits quick & easy suspension system system geometry setting. This XRAY concept was first introduced to the 1st XB8 and today ended up being carried to your 1/10 scale XB4. Making use of eccentric suspension bushings placed into aluminum suspension system obstructs, and additional suspension system shims, the XB4 suspension system system geometry could be entirely modified.