describe Specifications: This automatic hole puncher is 13cm long and 1.1cm in diameter. The set includes 2 automatic hole punchers and 2 spare hole punchers. It is small in appearance and easy to carry. High-quality material: the needle housing is made of high carbon steel, and the inner spring is made of stainless steel, which is waterproof and rust-proof, high strength and durable. Fast: The self-centering punch uses the internal spring to generate impact to open the item hole, no need to use a hammer to strike, and the operation is simple. Adjustable: The automatic needle loom has a built-in tension adjustment spring, and the cover can be adjusted clockwise or counterclockwise for a perfect fit. Wide Application: The automatic spring center punch can be used as a manual punching tool for wood, metal and glass; it can also be used to break car windows for emergency escape. feature: Made of high carbon steel and stainless steel, high strength, not easy to break, durable. The diamond-shaped pattern on the surface increases the friction between the hand and the handle, and the anti-slip effect is good. The high-strength spring can adjust the effect of the product. Small appearance, easy to carry. In an emergency, you can easily break the window to escape. Can be used on wood, metal or glass. Specification: Material: high carbon steel, stainless steel. Size: length 13cm, diameter 1.1cm packing list: 2 x Auto Punch 2 spare nibs suggestion: 1. The relevant dimensions of the product are measured manually, there may be slight errors, please understand. 2. Due to the shooting equipment and light, the product may have slight color difference.