Our 952R brushes are made of soft, grey goat hair.  These 5/16" diameter, 9/16" trim length, end brushes are constructed with a rubber ferrule which slightly increases the stated diameter, and also helps prevent scratching when used for interior polishing work. . One-piece ferrule construction ensures that the stem and ferrule will not become separated during use. Maximum operating speed: 25,000rpm. Sold in packages of 12, and are made in Germany.