If you are using the ZS axles and ZS knuckles these plates are designed to compensate for the slop elimination

If you are currently using the soft big block battery , this adaptor allows fitment into your R1 the weight of this adaptor is only 1.5g if you want to run your car light they will be black

If you are currently using the soft big block battery , this adaptor allows fitment into your R1 the weight of this adaptor is equal to the Big Block when using the HC 350's

Side Spring Set (4pair) BLACK=SUPER SOFT RED=SOFT BLUE=MED SILVER=HARD

MWX Formula R.1 Worlds Kit – Precision Redefined Engineered for elite micro-scale racing, the MWX Formula R.1 Worlds Kit delivers uncompromising performance through cutting-edge materials and race-proven innovation. Every component is designed to extract maximum speed, control, and durability on RCP tracks and beyond....