These Perma Grit sanding blocks are great, I use them to scratch build RC airplanes. Clog free on Balsa and Foam. They even cut CA glue! You know how hard it is to sand a blob of CA off of Balsa. The course side works like a rasp on the soft materials and the fine sides finishes it. Solid wings are now relatively quick and easy to sand to shape. Good stuff.

Excellent quality. The handle/holder is a perfect size and shape for holding over long periods of sanding. The 90 deg angle designed into it is perfect for insuring perpendicular faces. My primary use is for R/C scale aircraft.

I purchased the 140mm block. I have been using it for building my 3.4 meter RC glider. Its great! The coarse side cuts fast and watch out, some of the larger pieces of grit can leave deep grooves that will take a while to get out with the fine side. The fine side ALSO cuts fast, but leaves a finer finish. Ill likely be getting a 280 mm block and a contour block or two in the future. No signs of dulling after use with spruce, balsa, plastic, brass, aluminum.

Our team loves the construction of the sanding blocks with the strong back, sanding is smooth and easy. Great for large projects!

Great sanding block. Good size for arthritic hands to grip. Both aggressive or moderate material removal makes quick work of large projects, and built to last