Bones Wheels 84B SPF Scorpeedo P5 Sidecut

About Skate Park Formula (SPF)

Skatepark Formula (SPF) is a high-quality urethane specifically formulated to resist flatspotting on slick or smooth surfaces while maintaining a higher rebound for quicker response and faster roll. Skatepark Formula has a high resistance to abrasion without compromising hardness and slide ability. Simply put, Skatepark Formula wheels grip better on slick surfaces, are almost impossible to flatspot, and are the fastest, longest-lasting wheels on the market today. You won't find our Skatepark Formula from any other wheel supplier, so get a set and find out for yourself what the word on SPF is all about.

About Durometer B Scale

Shore Durometer A Scale is good, but it does not cover the entire range of skate wheel hardness and is limited because the scale goes from 1 to 100, and anything over 95A does not compute accurately. Shore Durometer B Scale is perfect for skate wheels because it is very similar to the A Scale but reads 20 points lower, allowing the useful scale to be extended by 20 points, covering the entire hardness range of skate wheels in one scale. It uses the same soft spring as the A Gauge, but the conical gauge needle of the D Scale. Because the spring is soft, the B Scale gauge needle does not puncture the skin of the wheel surface, resulting in the same reliable reading as the A Scale. Shore Durometer D Scale is designed for hard rubbers and rock-hard urethanes, not soft, bouncy urethanes used in skate wheels. It has a very stiff spring behind its sharp conical needle and often punctures the skin of the wheel being measured, resulting in a 5-10 points softer reading than is correct. Thus, Shore D Scale should not be used for wheels in the useful skate wheel range.