#4 or 1/8 inch diameter rivetsDomed head rivets are used when there is no access to the blind side of the two materialsMost common rivet headUsed to join two materials together quicklyAfter mandrel breaks off domed head is left exposedCopper and brass rivets are best for fastening copper or brass sheetsHat:Copper | Mandrel: BrassUsed both for their corrosion resistant qualities, as well as, their decorative lookPerfect for most environments because of their superior thermal and electrical conductivity Dome head rivets are mainly used in applications where there is no access to the rear (blind side) of the joint. Domed head rivets are the most common type of rivets. Rivets have a two piece construction; one is called the rivet hat and mandrel. Both the hat and mandrel are pre-assembled and ready to use. Dome head rivets are installed by using a riveting tool to draw the mandrel which causes the body to deform and clamp down on the joint. Upon reaching the designed clamping force, the mandrel snaps and is discarded. The mandrel side of the rivet, once the mandrel is removed, will leave the domed head exposed. WARNING: This product can expose you to chemicals such as nickel, lead, or chromium, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov Copper Pop Rivets Copper Rivets Blind rivets in this selection are made with a copper hat and a brass mandrel. Copper rivets are used for both their corrosion resistant properties and decorative finished look. Copper Rivets are commonly found in roofing, flashing and restoration applications. Brass Mandrels Brass is also valued for its corrosion resistance and superior thermal and electrical conductivity. In a rivet with a brass mandrel, this can be important because a portion of the mandrel remains within the rivet on the blind side of the application. Domed Head Copper pop rivets leave behind a smooth domed head. During installation, the mandrel snaps off as it is pulled through the body of the rivet on the blind side of the application.