Round Center Punch, Length (In.) 4 1/2 in, Hex (In.) 3/8 in, Standard Tool (Accessory Needed for Tethering), Non-Sparking, Non-Magnetic, Corrosion Resistant, 1-Piece Design, Aluminum Bronze Construction, -, For Use When Working with Flammable or Volatile Materials or When No Marring of the Target Item is Desired, Meets/Exceeds FM Approved