>Double spring system provides a softer initial rate at the beginning when both the main and tender springs are compressed together and deliver the desired firmer ending rate once the tender spring closes completely leaving only the main spring to deflect further. This spring system are soft enough to compensate for road irregularities ensuring permanent road contact and the spring system are firm enough to reduce body roll, squat and dive of the vehicle during cornering, acceleration and braking. 117mm spring w w Machined Delrin spring collar For On road use or Hi speed On road . tender spring 8 coil main spring 10 coil Wire size 1.4mm length 117mm comes in set of 8 will fit Stock and Savage GPM, Hot Racing Shock.