1. SIMPLE, SAFE, AND UNIVERSAL USE Our sharpener set is simple to use. Simply place the knife into the sharpening slot and enjoy a renewed edge in seconds. It is also easy to operate and suitable for all types of knives, including quality 'hard' steel knives. (Please pull the knife toward yourself multiple times and avoid moving it back and forth.) 2. STORAGETYPE POWER CORD Multiple charging options: household power outlets, portable power sources, computer USB, etc. Please note that the charger is located under the product base and can be seen when you open the cover. 3. 3SPEED SETTING AND BUILTIN CAPACITY BATTERY Three adjustable levels for , medium, and low grades. The builtin capacity battery allows continuous sharpening of over 50 knives. 4. ERGONOMIC DESIGN Our diamond steel sharpener features a 4stage sharpening system, enabling you to achieve an extremely sharp blade edge. The first stage of diamond sharpening repairs and straightens damaged blades, while the second stage performs a clean restoration and polish. Comfort is also considered in the design: the quality suction cup at the bottom provides a stable base and is comfortable and easy to grip.