Stops your carabiner from spinning around while belaying. It's heavily inspired by DMM's Belay Master.

After some field testing I have revised the design, ant this time it seems to actually work quite ok.

So far the design has been useable with all the DMM Twistlock HMS carabiners I have come across at the climbing wall.

Ralf's Box Printer

Doesn't Matter

No

0.25mm

25%

Don't use fancy infill patterns, rectilinear will do just fine, and won't stiffen up the part too much.

Seems like 2 perimeters is fine.

Pro Tip: Add a rubber band or an o-ring on both sides of the hinge, to keep it in place.