These 3d printed tools are for removing and installing valve lifter trays into BMW DOHC cam engines M50, M52, S50us, S52, M54, and M42.
They have small magnets built into them that stick to the top of the lifters (tappets) and prevents them from falling out of the lifter trays when removing and installing the trays into the cylinder head.
This greatly eases installation and prevents lifters from being lost, or damaged.
These engines are found in E30, E34, E36, E39, and E46 Z3 and Z4 bmw's
