I'm selling these whetstones to organize my collection, as I've accumulated quite a few for work. These are natural whetstones from Kyoto, for finishing. The five surfaces other than the sharpening surface are protected. I think they're also good for sharpening plane blades, chisels, etc. They're not very large whetstones, but if you're used to sharpening, you can sharpen large blades with them. If you take your time and sharpen carefully, you'll get a blade that cuts well. They're not perfectly square, so the size is a bit difficult to determine, but they're approximately 140mm x 85mm. The thickness isn't uniform either, but it's about 17mm to 22mm. #naturalwhetstone #naturalwhetstone #finishing #diy #carpentrytools #plane #chisel #kyotoproduce #koppa #kitchenknife