Summary For connecting two ends of GT2 2mm pitch timing belts together. This adds a 6mm screw hole specifically for attaching it to the t-slot rails of the Cobblebot system. This would be compatible with any OpenSource Build parts as they are all standardized. When you tighten down the screw locking this onto a rail it also tightens the grip on the timing belt ensuring a snug fit. This part should have been included in the kit from Cobblebot but wasn't. I used this to connect the timing belt to the print head carriage on the Y Axis. I Drilled a hole and tapped with a M5 x 0.8 thread. Then screwed the Short M5 mounting screws through the hole directly into the carriage.