The Hand Grinding Board is an adjustable and versatile tool ideal for woodworking polishing, car waxing, wall sanding, rust removal and paint removal. It has a rotary handle and groove design for easy adjustment of the curved surface, flat surface, and concave surface. With its ability to hold your desired angle shape throughout the sanding process, you maintain the same contours profile while sanding, allowing for dust-free sanding. It is easy to grip for even control when sanding flat, tight corners, contours, and other hard-to-reach areas and can be used in paint shops, detailing shops, woodworking wood furniture making, metalworking shops, industrial shops, and other household and crafting projects. Available in two sizes: 70 x 198mm and 70 x 400mm. Features: 1. Rotary handle + groove design on the back, you can flexibly adjust the size of the curved surface, flat surface, concave surface. 2. Perfect for woodworking polishing, car waxing, wall sanding, rust removal and paint removal, and so on. 3. Set your desired angle shape, and then the longboard hand sanding block will hold that angled shape throughout the sanding process, you maintain the same contours profile while sanding, allowing for dust-free sanding. 4. The hand sanding file block is easy to grip for even control when sanding flat, tight corners, contours, and other hard-to-reach areas. 5. Can be used sanding or polishing in paint shops, detailing shops, woodworking wood furniture making, metalworking shops, industrial shops, and other household and crafting projects. Specification: Material: Plastic Product Color: Yellow Product Size: 70 x 198mm, 70 x 400mm Product Weight: 210g, 500g Package Included: 1 x Dry Grinding Hand Push Board