The double helix is a design feature that has lead to improvements in the SuperPro product. The double helix is used in two applications. The first is on the inside of the bush and the second is on the outside diameter of the crush tube.

The first design of the double helix is used primarily on shackle bushes. The double helix provides a region for grease to travel along. This allows a boundary layer of grease to form between the inside diameter of the bush and the outside diameter of the tube. The double helix is extremely successful in greaseable shackles as the grease can travel from the centre of the bush along the helix and out to the grease grooves in the head of the bush.

Bullet grooves are incorporated in the design of SuperPro bushes to allow for variances in control arm or spring eyes.

The voiding and bullet grooves also allow for the transgression of displaced polyurethane into the volume of the grooves as load is applied during normal vehicle operation. Even though polyurethane is in a solid form when it is manufactured into bushes, its unique properties enable it flow in a manner similar to a liquid when loaded. The action of the bush flowing into its voids prevents the generation of harshness and NVH within the bush and its mount.

The tangential grease grooves in the heads of shackle bushes have reduced the friction between the head of the bush and the shackle plates. The grooves store grease, which is smeared around the mating surfaces when the spring shackles rotate forming a lubrication boundary layer. This has the effect of minimising head friction and reducing noise.