Did you use your carbon steel blade hard and put it away wet? Has a rust spot marred your supposedly stainless blade? KPL's rust eraser block is a medium-soft rubber eraser that embeds microabrasive particles that make short work of rust spots, pitting and patinas. Simply rub your blade gently with KPL's rust eraser block and watch rust stains vanish in seconds. We recommend starting slowly and rubbing in the direction of any grind marks on your blade! This product also works amazingly as a sharpening stone cleaner/refresher , where its medium soft texture conforms to crevices to quickly remove metal swarf and to unclog diamond, ceramic and natural sharpening stones to quickly restore their cutting power. Specs: • Grit: Fine • Composite: Medium durometer rubber/hi-density grit • Dimensions: 2” x 3” x .75”