7940 Siaair 6″ Foam Sanding Disc – 4000 Grit Super Fine

The 7940 Siaair 6″ Sanding Disc (4000 Grit) represents the pinnacle of fine finishing technology. Designed specifically for the final stages of surface refinement, this ultra-fine abrasive is essential for achieving a showroom-quality shine. At 4000 grit, it effectively removes micro-scratches and swirl marks left by coarser steps, creating a perfectly uniform surface that drastically reduces polishing time. Whether you are restoring automotive clear coats or finishing high-end acrylics, this disc prepares the surface for a mirror-like reflection.

Innovative Foam Backing for Precision Wet Sanding

What sets the 7940 Siaair apart is its integrated foam cushioning, which is particularly effective in wet sanding applications. The foam layer absorbs water to keep the surface cool and lubricated, preventing heat buildup that could damage delicate lacquers or gelcoats. This cushioning also distributes pressure evenly across the 6-inch diameter, allowing the abrasive to float over surface contours and body lines. This eliminates the risk of “cutting through” edges and ensures a consistent finish even on curved panels.

Long-Lasting Durability and Cost Efficiency

Engineered with premium aluminum oxide grains and a specialized resin-over-resin bond, these discs are built to resist clogging, even when sanding soft varnishes or mineral materials. The open-structure foam allows for efficient dust extraction during dry use and superior water retention during wet use. This advanced durability means a single 4000 grit Siaair disc lasts significantly longer than standard paper abrasives, providing a cost-effective solution for professional body shops and industrial finishers looking to optimize their polishing workflow.