Easy, safe and universal use Simply insert the knife into the sharpening slot and pull the blade through in one forward direction several times to achieve a sharp edge in seconds. Do not pull back and forth. Compatible with all knife types, including quality hard steel blades. 3speed adjustment and builtin battery Three sharpening speeds: , mid, and low to suit different steels and edge conditions. Builtin largecapacity battery can sharpen more than 50 knives on a single charge. Ergonomic design Diamond sharpening system with a fourlevel sequence. The first stage repairs and straightens damaged blades; the second stage restores and polishes for a clean edge. Stable suction cup base provides a firm grip during use, and the ergonomic handle offers comfortable handling. Storage type power cord Flexible charging options including household outlets, power banks, and USBenabled devices. The charger is stored under the base; access it by lifting the lid to connect power. Use scenarios Home kitchen: quickly refresh everyday chef knives, utility blades, and such between meals to maintain a sharp, ready edge. Outdoor or travel: USB or power bank charging enables sharpening during camping, caravanning, or on the go for reliable edge maintenance. end or hard steel knives: ideal for preserving edge quality on blades that require careful, controlled sharpening. Notes For results, pull the knife through the sharpening slot in a single forward direction several times, and avoid a backandforth motion.