• effortless caster checking • Precise calculating • can be utilized ahead & back • Fits X4 & X4F Precision moulded composite caster gauges for checking the caster angle of XRAY X4 & X4F. May be used both within the front- as well as the backside associated with the car. To be used alongside the HUDY Universal Exclusive Set-Up System For 1/10 Touring Cars.