The unique, one piece design of these Standard Plastic Expansion Rivets provides an enlarged bearing surface that will hold panels together securely without restricting thermal expansion. These rivets quickly insert from either side of the assembly and can be used with most standard pop rivet setting tools. As the tool pulls the pin through the body, it draws the panel together. When set, the pin breaks off even with the head, leaving an attractive, finished appearance. They are particularly effective for soft materials such as rubber, urethane or padded fabrics.