M113K Double Pulley
This double pulley replaces the stock one (A1132020419), known to not last long and having different issues.
The outer pulley runs on two bearings. It permits to have almost none perpendicular play, so the supercharger belt stays always where it should. Also, double bearing setup is more resisitive to high loads, making the pulley last much longer than the stock one.
Both pulleys are made of aluminum, that makes them easily servicable in case of a bearing failure.