Description:1. Designed with a cylindrical shape. These handy sanding accessories provide great performance, durability and versatility.2. Fit for grinders and rotary tools. Can be used for deburring, grinding, shaping or carving for wood, plastic, metal and other DIY production.3. Rubber expansion-drum mandrels easily slide sanding sleeves over drum and tighten screw to fix it.4. Widely used in home improvement, art craft, wood, metallurgy, machinery, shipbuilding and light industries.Specification:Material: Aluminum OxideSanding Sleeves Size: 1/4-inch x 1/2-inch (Inner Diameter*H)Drum Mandrel Shank Diameter: 1/8-inchDrum Mandrel Head Diameter: 1/4-inchDrum Mandrel Total Length: 39mm / 1.54-inchGranularity: 320 GritPackage Content:100 Pcs x 1/4-inch Sanding Sleeves2 Pcs x Drum Mandrels.