This polishing wheels kit can be used for a variety of metal,hardware,iron,aluminum,copper,stainless steel,jewelry,automobile,hardware,plastic and other Derusting,Sharpening,Polishing,Meet all your polishing needs APPLICATION Corunbum Sand Grinding Wheel Dimension: Wheel diameter: approx 75mm( 3 inch). Wheel thickness: approx 20mm( 0.78 inch). Arbor hole diameter: 10mm (0.39 inch). Rough polishing for surface of most of materials. Wool/Fiber Buffing Wheel Dimension: Wheel diameter: approx 75mm( 3 inch). Wheel thickness: approx 20mm( 0.78 inch). Arbor hole diameter: 10mm (0.39 inch). Medium polishing for surface of most of materials. Cotton Polishing Wheel Dimension: Wheel diameter: approx 75mm( 3 inch). Wheel thickness: approx 15mm(0.59 inch). Arbor hole diameter: 10mm (0.39 inch). Fine polishing for surface of most of materials. PACKAGE CONTENTS: 3'' Corunbum sand grinding wheel x 1 3'' Black fiber buffing wheel x 1 3'' Wool felt buffing wheel x 1 3'' Yellow cotton wheel x 1 3'' Cotton polishing wheel x 1 WARM PROMPT: It is best to saturate the abrasive stone grinding wheel with water or oil before use, and add it appropriately during use.It is recommended to use cotton buffing wheel with polishing compound !!!