Socket Head Cap Screws M3x12mm can be used especially in hard-to-reach places. They are perfect...HobbyStore
Linear bearing LM12UU
These bearings, however, are a good budget alternative. Closed linear bearings have a wide range of applications in linear motion, in particular in the construction of popular 3D printers
The outer jacket is made of bearing steel. The basket is made of plastic. The bearings have a seal on both sides, which prevents dirt accumulation.