Swiss made set for removing burs and burnishing holes after drilling and reaming. Also used for countersinking tapered shoulder screws. Assortment of 4 polished hardened steel double ended wheel countersinks with nickel plated brass handle. Sizes 4.50mm/5.00mm, 3.50mm/4.00mm, 2.50mm/2.80mm and 1.80mm/2.10mm. Useful for finishing off a clockmaker’s bushing installation. Great for jewelers & hobbyists who perform precision work.