Simple flex plate stops using either M3 or M5 screws, reversible design has holes for both options.

I ended up using socket head cap screws, these don't take up and build volume and work well.

If you use button head cap screws you do lose like 3mm of your Y axis, but this helps keep you from sliding the bed over the screws. If you have compromised fine motor skills this might be good for you. Button head cap screws also prevent you from putting the flex plate under your sex bolt z end-stop on accident.

To install loosely fasten to screw posts with your M3 or M5 screw started into them and place your flex plate flush with the rear of your bed, slide the blocks so that the screw is touching the build plate and tighten the m3 screw to the extrusion to secure the block.

You should print them in a high temp filament like ABS or ASA as some heat will conduct through the screw.

If you use a button head cap screw adjust your slicer software to drop 5mm from your Y axis or avoid placing parts there. Make sure your Z lift before homing XY is at least 5mm to avoid any possibility of nozzle crash (no changes needed to basically any example configs for Klipper).

Required hardware

• For fastening: 2x M3x16 screw, 2x m3 t-nut of your choice (slide in t-nuts if you are a masochist).
• For flex plate stop m3 or m5 SHCS or BHCS from 16-30mm, 20mm ideal.

STL file will produce working parts for either an M3 or M5 configuration, no adjustments or mirroring needed.