Most soft polyurethane compounds achieve lower durometers at the expense of increased rolling resistance, wasting precious power and dramatically shortening shifts. It is analogous to letting the air out of your car tires: you get a smoother ride, but it comes at the expense of increased battery drain and sluggish performance. SPS uses a different approach to achieve traction and a super smooth ride that helps trucks glide down warehouse isles. Like a toy super-ball, SPS returns energy when compressed, minimizing ampere draw and boosting productivity. Add sensor siping and you have the ultimate freezer compound.