Sebenza 25 for the asymmetric free rotating stop pin/spacer. If not tightened enough it can rotate stopping the blade. Enough tightness to ensure non-rotation and the blade gets dragged even though that's supposed to be controlled by pivot tightness. I also had to deburr one out the pivot bushings. Their paperwork included decals but no warning about the flat side on the pivot pin. I needed BF for that.