Sanding Sponge Assortment of 6 ★For rough trimming and shaping Grade:#240, #320, #400, #600, #800 and #1000,1 pc each For plastic only.These are the thinnest version of Kamiyasu SandingSticks. It's easy to be cut and bent to file the spotwhich is hard-to-reach and curved parts of plasticmodel kits. Their thinness allows you to even filewith tweezers.