R&G Fork Protectors: An essential, low cost and easy to fit product that helps protect the lower part of the forks and front brake calipers. For most bikes, R&G Fork Protectors mount through the hollow of the wheel spindle with two sliders at either end that slightly protrude in order to help prevent suspension and brake components making contact with the ground. The main construction of the protectors is High Density Polyethylene (HDPE) -- the same material used as R&G's main Crash Protectors.