Stock skid tends to break easily, this replacement is designed to be put under the zip ties holding the ESCs. The last photo shows an alternative way of assembly where the ESCs reside on a double sided adhesive pad and the leg is zip tied closer to the motor. You can also put a heat shrink on it for dampening. These ESCs are fragile, so zip tie with a leg can produce additional stress, consider using this way. While it may look fragile, it's very tough and should survive most of the crashes. 4 pieces weigh under 2g (print with zero infill and thin perimeter, for Cura I set shell thickness = 0.4 = nozzle size). Super-X 125mm Micro Brushless QuadcopterRCGroups Forum thread
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