Made of high-quality carbon steel, it has high hardness and strength, and is also very durable. Automatic adjustable wrench: automatic locking, adjustable jaw capacity, easy to use with one hand, simple and practical. A set of two sizes of wrenches: the 26.5cm/10.5 wrench has a jaw capacity of 14-30mm/0.55-1.18, and the 38cm/15 wrench has a jaw capacity of 30-60mm/1.18-2.36. It can be used with different nuts such as prism, square, diamond, etc. The 14-60mm specification can meet your different needs. These adjustable wrenches also have hardened serrated teeth on their jaws. Hard teeth can bite into the softer metal of a circular tube and provide the grip needed to rotate the tube. The TPR ergonomic handle secures your grip at the strongest point and keeps the user's wrist in the normal position to reduce pressure and improve work efficiency. The tapered pry bar design at the end of the handle makes the wrench more useful. Material: High carbon steel, thermoplastic rubber (handle) Large wrench -38cm/15 Small wrench -26.5cm/10.5 Capacity of wrench jaws: Large wrench -30-60mm/1.18-2.36 Small wrench -14-30mm/0.55-1.18