Not just for concave surfaces, these curved blades keep the blade corners off the surface and allow more control at the scraping edge. They can be used with a natural rotating action, varying the pressure and angle of attack.
Originally developed for the graphics and auto-detailing industries, they are made from a material with natural lubricity. Soft enough to be used on non-stick cookware, automotive paints and other delicate surfaces, they resist common solvents and are slightly flexible.
The blades are 1 9/16" (40mm) wide and fit the 2 3/8" and 6" holders (sold separately) as well as many standard razor blade holders.
Sold in packages of 30 blades in a dispenser that also captures used blades.