LMF8LUU IGUS-profiled bushing

The bushing is an alternative of the LMF8LUU linear bearing (Anet A6 Z-bearings). This reduces vibration and improves the smoothness of the stroke, which positively affects the quality of the print. Also the plastic bushing is much lighter than the standard bearing LMF8LUU.

The bushing has original IGUS profile ([RJ4JP-01-08](https://www.igus-cad.com/ccHandler.aspx?ArtikelNr=RJ4JP-01-08&OpenTree=1&pgid=102013))
The inner diameter of the hole in the model - 8.1mm