hi... this is a thing that i made for a friend. his HPI Trophy 4.6 crashed and this little plastic shock cap broke in halfes, so i created a new one. it works pretty well and is very stable. original HPI part number: 101161 i printed it with PLA (you will need 10cm filament and it took 4minutes to print). its very stable and it fits perfectly ;) you need to drill the hole to 6mm.