Metal Hole Punch Pliers with 1.8MM Round Hole. Our 1.8mm hole punch pliers will punch copper or silver as thick as 18 gauge. With ergonomic handles and tempered replaceable pin these pliers will save you time and money. The pliers are made of thick carbon steel and come with an extra replaceable pin. The 1.8mm hole with accommodate up to a 14 gauge wire. These are must for any beginning stamper's tool kit.