Material: UHMW-PE (ultra high molecular weight polyethylene), aircraft grade aluminum NO CUT or plastic fairing modification required Fit Models: KTM 2017 - 2023 790 Duke / 890 Duke This purchase is for a set of engine case covers (one LHS and one RHS). The covers are designed to help protect your bike's engine case and stator cover in the event of a low-side. The material of the puck is made of UHMW-PE (ultra high molecular weight polyethylene), a tough plastic with good strength, wear resistance and dimensional stability. It is more dimensionally 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 sliders since it can absorb more impact force onto itself and therefore reduce the impact on the frame and engine. 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.