SPECIFICATIONS • Material: Diamond lapped on aluminum • Grit: 140 (Extra Coarse) • Dimensions: 8 1/4 #34; x 3 #34; x 3/8 #34; ht (21cm x 7.5cm x 1.1cm) • Please be advised that there are counterfeit products in the market. #34;Atoma Economy #34; by Tsuboman is the economical choice for diamond sharpening plates. Unlike whetstones and other ceramic sharpening stones, a diamond plate will not wear down or concave over time. You also don #39;t need water to sharpen your knives. Atoma will remove steel very quickly, and the plate will never clog because it is made using a special patented dispersion technique. You can even use it to flatten sharpening stones! Use this coarse, 140 grit plate to fix minor chips and to recreate an edge on your blade.