Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Warning: Grooved

This is a grooved, rather than a straight steel. This means it is taking significant portions of metal off your edge with each pass (that's the job of a sharpening tool, not a honing tool!). The grooves risk significant damage to your blade. The grooving is sort of apparent from the photo, but it should be made more explicit. Consider yourself forewarned!