3-pack. Diablo Starlock bi-metal oscillating blades feature application specific designs that deliver maximum durability and longer life in clean wood applications. These high-performance blades feature an ultra-hardened cutting edge to deliver up to 5X longer life than standard blades. Curve contact edge creates a pilot for precise, clean plunge cuts with less vibration. An optimized Japanese tooth design and Black I.C.E. (Industrial Cooling Element) keeps the teeth cool and build up free for fast, clean cuts. Tool free quick-change interface fits Fein and other Starlock tools; also compatible with most non-Starlock multi-tools.