Hole (pin) size is approximately 1.5mm which will accommodate up to an 16 gauge wire (with a little wiggle). These pliers are made of thick carbon steel, feature ergonomic handles, and come with an extra replaceable pin.
These hole punch pliers will punch through Copper, Sterling Silver and Aluminum up to 20 gauge. They will punch Brass, Silver Filled and Gold Filled up to 22 gauge. They will punch Nickel Silver up to 24 gauge.
Replacement pins for these pliers are also available.
I love the quality of these pliers, and especially the price. They punch great through the blanks!
These pliers will leave a small mar on your metal right next to the hole. To avoid this, tear off a small piece of thick paper (like card stock) and punch a hole in it with your plier. Let the paper stay on your pin sitting up where the pin connects to the plier. This will act like a cushion.