This allows you to use t slot bolts in a miter gauge slot. I use them as hold downs on the table saw and drill press. I originally made these as a prototype prior to making them out of aluminum, but they have proven to be sturdy enough that making them out of metal hasn't yet been necessary.

I printed these out of PLA and used 100% infill. I was able to break one at 50% infill.

Print, insert a 1/4-20 t slot bolt in the underside and slide into a miter track.