Some tabs for holding the glass on the Onyx rev. 7 heat bed on the Rostock Max v2. It MIGHT work for other revisions.

You screw them into the EMPTY bed holes where the binder clips usually go and then put the glass on. The hole is a bit smaller than 3mm so you can just thread the screws into this without worry. You SHOULD be able to put the glass on and off without removing these, so print them in ABS for a bit more flex and temperature resistance. Print 6 of these, or more for spares. They are pretty tough in ABS, although you CAN break them by hand so careful. Use flat panhead screws like the ones you installed the bed with so the glass doesn't hit the screws.

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rostockmaxv2, seemecnc, onyx