A breakstem, blind sealing, self-plugging rivet is a type of blind fastener that is used to create a permanent connection between two pieces of material. It is called a "breakstem" rivet because the mandrel, or stem, of the rivet breaks off after installation, leaving a smooth, flush finish. The self-plugging design of this rivet allows it to be installed in materials as thin as 0.020" (0.5mm). The sealing sleeve expands after installation to create a watertight and airtight seal.