>Grobet Swiss pattern Precision Needle Files are manufactured to precise production standards, using a combination of machine cutting and hand craftmanship to produce the most accurate,best cutting, and longest lasting files in the world. They are made of the finest heat-tempered,chrome alloy steel and have the "right" feel,action, and balance desired by all true craftsmen. Grobet Swiss pattern Precision Needle Files deliver superior performance on all metals. Simply the best you can buy!!