Center punch with blue caps: Made of high-speed steel, strong impact resistant, wear-resistant and rust-resistant to extend the life of the punch. High speed steel hardness: HRC58~60. The center punch cap is made of hard engineered ABS plastic. Blue adjustable impact cap can be increased or decreased. The punch body has a deep knurled grip for easy handling and better one-handed control. How to Use: Use the heavy head to mark the center of a hole you want to create. Firmly press the handle and press in the direction of the punch. After pressing the punch into the shank for a short time, the powerful spring will vigorously eject the punch. Center Punch with Red Caps: The body of the punch shank is made of chrome plated steel for maximum strength and longevity, which allows high impact force and resists corrosion; spring loading center.Unique design: non-slip knurled surface on spring rod allows for comfortable working and reduces user fatigue. Precision center tip increases control for more precise holes.Wide Application: Automatic center punch is suitable for a variety of tasks, such as panels on materials, glass breakers, belt awl , marking on the wall and so on. The spring-loaded tool walks your workpiece with a dimple to give you a starting point that keeps screws and bits from moving around; use this automatic punch for metal, wood, glass, canvas, plastic and leather.