Freebutton 21mm four holes
Thingiverse
6 model
Free
FreeAnycubic Vyper / Kobra Max - PTFE guide clip (21mm, flat)
Thingiverse
FreeMini Desktop CNC Z-Carriage 21mm Bearing Option for LM12UU
Thingiverse
FreeEnder-3 Pro Y-Axis 21mm Extrusion Extension
Thingiverse
FreeAM8 Multi X Axis Mounts (17mm and 21mm for now)
Thingiverse
FreeHole Test 2.0mm to 8.9mm by 0.1mm
Thingiverse