Power Rotary Scissors Idech ASK-MW23. Fits Stens brand aftermarket item which replaces a brand name product. This is not an OEM product. Fits straight shaft trimmers with solid drive shaft; vertically as an edger. Includes standard 18/15 tooth blade set. Patent pending design prevents kickback and thrown debris. Bottom disk is designed to rest on the ground and prevent scalping. Blade rotation stops quickly when throttle is released. Safer to use around areas with sand or water, can even be used in shallow water. Replacement blades available in standard 18/15 tooth with optional sets available of 21/18 teeth or 28/24 teeth. Includes adapters to fit a variety of common trimmers. Includes adapters: 6mm-10 teeth, 7mm-13 teeth, 7mm-7 teeth, 8mm, 9 teeth and 5.2mm-square.