Air-powered blind rivet installation tools compress blind rivets to join two pieces of metal. Rivets are placed into a pre-drilled hole, and the tool compresses the end and breaks the rivet mandrel to leave a clean surface. The rivet mandrel is then ejected from the tool. Blind rivets (sometimes called pop rivets) can be installed when there is access to only one side of the workpiece. Air-powered tools are typically lighter than cordless tools, helping to reduce operator fatigue when used for long periods of time.