5 Bergeon Swiss Watch Screwdrivers Great For Watch, Electronic & Eyeglass Repair. This is a new set of 5 Bergeon slotted screwdrivers Great for watch, electronic and eyeglass repair. The tips are made from a completely non-magnetic chrome alloy while all other parts are completely non-ferrous and non-magnetic. Includes a replacement tip for each size. The tips are flat and measure: 0.5, 0.6, 0.8, 1 and 1.2 mm.