This Package Of 6 Balata Rubber Cylinders Are All Pre-mounted On 1/4" Shanks, And Are Each 1" X 7/8" In Diameter. You Can Use These Balata Rubber Cylinders In The Same Way You Would Use Any Other Rubber Cylinder. These Cylinders Area Made Of 100% Genuine Balata Rubber.* Package Of 6 Pieces * 1" X 7/8" Diameter * Pre-mounted * Includes 1/4" Shank * Compatible With Drill