We believe that conventional skidtubes are under-designed for the types of landings most helicopters encounter. Conventional skidtubes are ill-equipped to face the critical loading conditions encountered when landing on uneven ground. Under these conditions, simple round tubes tend to puncture, dent and bend because they cannot maintain their shape. DART Aerospace's revolutionary patented Round-I-Beam™ technology combines the conventional round tube with the strength of the I-beam made from 6061-T6 aluminum. In DART Aerospace skidtubes, the central I-beam web absorbs most of the impact on landing so the tube maintains its integrity. Even with the addition of a central web, the weight is comparable to that of conventional skidtubes. The wearplates are installed with a corrosion resistant compound between the skidtube and wearplate (no gaskets or sealant required). Comes standard with full-length stainless steel tungsten carbide welded wearplates. *Comes with 4 full-length Stainless Steel wearplates & 2 additional wearplates at the saddle locations. Saddle wearplates and AFT most wearplate are tungsten carbide welded. Pre-drilled for compatibility with Bristol WSPS (p/n 965-19500-101) Skid Deflector. Can be made compatible with DART (Apical) Tri-Bag Float System p/n 644.1801/1802/1806/1807/1808/1809 when installed with D135-751-101 & 644.1805. Must be installed with L321M1003102 FWD crosstube and L321M1002101 AFT crosstube.