Its a tested ropegrab/ascender to be used as replacement for a prusik. DO NOT USE AS A SOLO SAFETY DEVICE. The Shunt pro is tested for 200 LB static load. To get the tested strength print in the orientation shown with 3 perimeters and 25% infill. This can be used for hauling systems. The Shunt pro work like a Petzl Micrograb. Made for 9.5mm dynamic rope. Purple.co is a fake company. The bolt is a M8 by 3.5cm