90 degree stop block for use in T Track. Allows for repeated, precision cuts with your miter saw. 3/8" guide on bottom of the piece minimizes wobble inside the track.

I use this track: https://a.co/d/iGcBabm

Requires track knob hardware, I already had this on hand: https://a.co/d/iOF7pqL

Alternatively you could also 3d print your own knob (like these: https://makerworld.com/en/models/146357#profileId-159376) and use ¼"-20 by 1-½" hex bolts with accompanying nut / washer.