Velcro Sanding Strips 70 x 420mm P40 x 50. These sanding strips are suitable for sanding profiled surfaces. It is a light, flexible latex paper suited for both dry and wet sanding. The special stearate coating prevents clogging and pill forming. Coarser grits are recommended for dry sanding of putty and finer grits are suitable for sanding of surfaces with primer and lacquer.