Features:Self-expanding cushion is easy to install and designed to hug sleeves for a tight grip, keeping sanding paper in place for an extra fine finish. Standard size drums are common and compatible to use with rotary tools such as drill presses and hand power drills. It comes with strong storage case for quick access and protection. Quality construction built is long lasting, lightweight and durable for sanding holes, contouring edges, and buffing out irregular shapes. Ideal accessory for home improvement, hobbies, DIY, carpentry, wood working, and many more. Specifications:Quantity: 20pcsWeight: Approx. 910g 4pcs Rubber Drum Sizes Diameter Height ShankDiameter 1/2inch 64mm / 2.52inch 3mm/ 0.12inch 3/4inch 64mm/ 2.52inch 6mm/ 0.24inch 1inch 64mm/ 2.52inch 6mm/ 0.24inch 1-1/2inch 64mm/ 2.52inch 6mm/ 0.24inch Package Included:1pcs x 1/2" Rubber Drum1pcs x 3/4" Rubber Drum1pcs x 1" Rubber Drum1pcs x 1.5" Rubber Drum2sets (8pcs) x Coarse Sleeves (80grit)2sets (8pcs) x Fine Sleeves (120grit)1 x Case Note: Only rubber drums, sanding sleeves and case, no other stuff included..