This heavy-duty rivet g-un features a high-quality steel body with excellent rust resistance. Thickened steel and a chrome alloy wrench ensure greater durability and a longer service life.【Four Rivet Sizes】- This rivet g-un comes with four interchangeable rivet heads: 3/32 inch (2.4 mm), 1/8 inch (3.2 mm), 5/32 inch (4.0 mm), and 3/16 inch