Our 3M™ Hookit™ Center Water Feed Disc Hand Pads have a proprietary feed system that dispenses water for wet sanding of plastics, primer surface, paint, fiberglass and other materials. The water flushes residue off of the sanding disc which keeps it from loading. These firm, yellow disks feature 3M™ Hookit™ hook-and-loop attachment surfaces, and are available in both contoured and bullet shapes. Easy Hook-and-Loop Attachment 3M™ Hookit™ hook-and-loop feature makes disc attachment, removal, and re-attachment easy and facilitates use and re-use of the disc for the extent of the abrasive life. Hookit™ disc pads have J-shaped hooks of the type most commonly used in everyday hook-and-loop applications. Hookit™ disc pads grip the brushed nylon loop backings of 3M™ Hookit™ discs and provide a finer finish than adhesive backed discs. The Hookit™ system is designed for work spaces where adhesive backed discs may become contaminated by dust, dirt, or water. Waterproof Advantage 3M™ Wetordry™ products are backed with a proprietary durable waterproof paper backing that supports both wet and dry applications. Lighter weight than cloth, and smooth rather than textured, paper backing is preferable for lighter applications such as finishing and paint prep. At the same time, many such applications produce a significant amount of dust, clogging the abrasive points and creating an inferior work environment. These effects can be minimized by sanding with water to rinse dust away from the workpiece and the abrasive surface.