Hpi Super Star wheels come with the offest hexes that fit inside where you mount the rims to hex hubs then chassis. I really needed those because stock, the wheels were so far sunken in on my shell it was crazy I have an Hpi 200mm Nissan Silvia S15 and its already a really wide body so putting in those rim spacers made my tires become flush with my shell without rubage, and it now looks just as it should. Oh and I had to buy the wider 6mm aluminum hex hubs just for this to work as it was, and they were surprisingly cheaper than the 4mm hex hubs in aluminum, but the smaller set came with a bunch of shims and an extra hex hub so I guess thats why but I hope some of that helps you.