PACKAGE: 2 x center punch + 2 x replacement punch, the center punch is 130mm long, 12mm in diameter and 4mm in tip diameter, enough for your daily replacement and use. HIGH QUALITY: The automatic punch is made of high speed steel punch and carbon steel handle, high strength, high hardness, strong and durable, not easy to wear, and has a long service life. > EASY TO USE: Simply adjust the spring loaded center punches to your desired spring tension, press down hard on the handle for automatic center punching, you can make precise marks without using a hammer, easy to use. NON-SLIP DESIGN: It is ergonomic and adopts non-slip diamond pattern, which can increase the friction between the hand and the positioning punch handle when using, providing you with comfortable and precise operation. WIDE USAGE : Self-centering punches are suitable for punching positioning holes in wood, metal, glass, plastic, steel, leather, cardboard or wall etc. ; It can also be used to break car windows, so you can use it in emergency escape situations.