Back surprise spring 82mm - 4-Dots provides a mixture of progressive & linear traits. The smaller design helps to achieve reduced ride height on high traction tracks. The springs are somewhat modern, but under more compression modification characteristics to are more linear. This gives exemplary feeling and feedback in all different track conditions. These XRAY surprise springs, as with any other XRAY springs, are manually measured, chosen and matched into pairs to guarantee precisely equal length and damping traits.