These tips are marketed as anti-skid tips for Bergeon 30080 screwdrivers, however, they are so thick that, instead of anti-skid, they are like drift tips They are more expensive than Bergeon tips too, so all in all they were a pretty bad purchase, I feel like these are more domain specific, for example they go along well with 550 series movement screws, but they don't even engage with 620 series small ladies movement screws False Marketing: Kwong Yuen Tips: Bergeon 30080 Tip:
Hollow ground blades like these aren't really needed for the typical flat head screws in watches. They are more difficult to fit properly to the slot thickness, so really there's no advantage to them for most work. Where they do work well is for round head screws. For example, the screws that are used to hold the crown lock on a Panerai. These blades give you excellent engagement with these screws, and prevent chewing out the very top of the rounded head. It's basically the only place I use a hollow ground blade. Cheers, Al
They seemed very domain specific to me, thanks for the insight I originally wanted them for the ratchet wheel screw but I'm guessing they won't even fit - however they fit other 550 series screws well, grips them so the screwdriver can only be lifted upwards