i3 Rework X-Carriage for GT2 & T2.5

Remixed of the i3 Rework X-Carriage.

The idea behind this design is make attaching your belt much easier and without using zip ties. belt-tightening is also much easier.

It works with both T2.5 and GT2 belts.

I also provided a test sample so that you can print and test fit your belt before printing the whole thing.