This is a… I don’t know how you call it, let’s say crimp, used to “terminate” the end of a GT2 belt typically into a small loop end for hooking onto something ot whatever (this is not a “joiner” for joining open loop belt into a closed loop, it just is used to terminate open loop belt).
And… I honestly don’t really know how you’re supposed to use this without some sort of special tooling.
I’ve included a photo of a “pliers job” I did with one, it’s not pretty, I don’t know what it adds to the party, it’s a bent bit of metal.
No idea of composition.
Some 3d printers might use this sort of clamp to attach an open loop belt to an X or Y carriage.
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