This cleaning block allows you to easily remove residue on your bonsai tools. Acts as a unique alternative to sandpaper, emery cloth, steel wool and rubbing compounds making it more gentle on your tools. Grit easily removes sap and other hardened materials on tools. Leaves a nice shine when finished. Embedded medium grit is perfect for removing large pieces and stains. Simply use block like an eraser, rubbing firmly on wet or dry surface. Highly recommended. Makes cleaning your tools fast and easy. Made in the Germany. Non-toxic.