The special concave hammer heads minimizes with screw threads, paired with resistant alloy steel and ergonomic grip for fatigue resistant operations during prolonged use Perfect for securing anti theft doors / window, mounting air conditioners, or fastening structural fixtures where precisions and bolt integrity are critical Engineered for precisions and durability, this expansion bolt hammer punching features a unique concave head design to thread damage while ensuring secure installations with alloy steel construction Combining anti slip ergonomics, enhanced wear resistance, and universally compatibility with power drills, this punching optimizes efficiency in both commercial and residential installations Ideal for professional installers, HVAC technicians, and DIYer enthusiasts requiring tool for heavy duty anchoring tasks in construction or home improvement projects, Manufacturer: JSGHGDF