1. Made from chrome molybdenum for increased durability, blackened phosphate coating for corrosion protection. 2. Designed for the safe removal of bolts that have rounded off, rusted or painted over. 3. Suitable for hand and power tools. 4. Can be used with 3/8" breaker bar/ratchet and also has flats so that they can be used with spanners or wrenches. 5. Complete with an useful carrying case for quick and easy storage.