This is an awesome spinning fan gauge. These really cool gauges will spin like a fan when air is passing through the gauges. These gauges are made up of 316L Surgical Steel. The gauges are double flared. These gauges are available in size 0 gauge, 00 gauge, 1/2 inch, 9/16 inch, 5/8 inch, 7/8 inch and 1 inch. This item is sold individually. Item is completely nickel free.