12 Piece Set #3 Stainless Steel Rolled Rim Spur Grommets The hole size after setting is 7/16" Inch and the outside diameter is 7/8" Stainless steel grommets require more force to set than regular grommets. Stainless Steel Grommets are different from regular grommets. Even though these grommets are "Rolled Rim Spur" by classification you will need the #3 Plain Grommet setting tool for correct installation. Depending on the brand of tool your Spur Grommet tool may work with these grommets. Will pierce most fabrics without pre-punching a hole, while setting the grommet and washer in the same action. Designed to withstand the harshest environments, our stainless steel self-piercing rolled rim grommets with spur washers are the best product available for corrosive applications. These grommets can be installed through several layers of tough material and can be attached with hand dies in low volume situations. Setting Tool not included but is available. Send us an e-mail if you need the tool and we'll get back to you with the latest price. We Ship Internationally! Northwest Tarp Canvas Check Out Our Quality Tarps! Have a Nice Day!