Condition: New Material: UHMW-PE (ultra high molecular weight polyethylene), steel, aircraft grade aluminum NO CUT or plastic fairings modification required Fit Models: Yamaha 2008 - 2020 XT250 / XT250XPDF Instruction:This purchase is for a set of frame sliders for the above bike model. The bar is made of steel. The puck material is made of UHMW-PE (ultra high molecular weight polyethylene), a tough plastic with good strength, wear resistance and dimensional stability. It is more dimensional stable than Nylon and used in many industrial ball bearing and friction reducing applications. Compared to Delrin, it is softer but tougher. Delrin is harder but more brittle. It is an ideal material for slider since it can absorb more impact force onto itself and therefore reduce the impact on the frame and engine. The slider pucks can be inexpensively replaced in case of a low-side. We use highest grade commercially available 12.9(177,000 psi in tensile strength) wherever possible. Rest assured that you are getting the best material commercially available.