Instruct: Classify the given Amazon review into positive or negative sentiment.
Query: Robert Larson Honing Guide Thumbs Down

This honing guide does not work with chisels that have flat sides. All my chisels have flat sides? Common sense 101, cannot fit a square peg into a round hole. The sides of the chisel are flat and the honing guide notches which are supposed to grip the chisel are small bevels. End result, the chisel cannot be clamped. Screw head knurls have sharp edges and the head is too small in diameter to apply sufficient finger pressure to clamp. Wasted money, returned to mother nature. Given sufficient time it will break down and leach into someones water supply. Sorry