Lerdge optical endstop mount.
Will fit either double rail or single rail extruded aluminum, with sensor centered over single rail.
Need two M3x10mm bolts and nuts to secure sensor to mount.
If print is too tight for the nuts, I use a soldering iron to push them in.
I made these for my Tronxy 500 and 600 printers, replacing all electronics with Lerdge.