Canons and Magnums (Only 0.6”): The canon is the same shape as a barrel, but with a slightly larger outer diameter. It is designed to fit more tightly in normal bushing seats, and it works well with trucks with slightly larger bushing seats. Canons work with large cup washers and small flat washers. The Magnum is designed to replace Chubbys in Paris or other trucks with slightly larger bushing seats. It works with large flat washers. Plug Canon .6": The Plug Bushing is based off the shape of the Riptide Canon, but with a plug like insert that fits into the hanger of the truck. This Plug Shape was originally designed to work best with Pantheon Stylus Trucks and Valkyrie Cast Trucks, but this shape is also compatible with the following trucks that we have tested them with: Pantheon Stylus Valkyrie CastCaliber 3 RKPBear Gen 6APS is our most lively feeling urethane with high rebound and lean. It will turn 10-15% more than the same durometer of other brands. It has the widest range of durometer from 97.5a (super hard) down to 60a (really soft), and is a great starting place if you're new to changing your bushings.