The RDRP Brass RR Suspension Mount for the Xray XB4 series of cars is a direct replacement for the kit's lightweight part. It adds valuable weight especially when running in low-traction conditions or when the track is getting bumpier. Machined from black-coated brass and sporting gold-colour chamfered edges the part weighs in at 15g which shifts the weight bias to the back for improved traction especially in low traction conditions and when the track is getting bumpier. The RR mount is a direct replacement and usable with the Xray suspension inserts.