Abstract: A blind riveting and sealing system for sealing circular openings in sheet type materials and for securing together plural sheets. Each of the sheets to be secured together has an identical size hole for accommodating the rivet of the invention in a force fit relationship. Additionally, one of the sheets has a reduced diameter step in the rivet receiving hole to form a resilient annular locking flange. The rivet of the invention has a necked down portion to form a beveled seat face. This beveled seat face engages the resilient annular locking flange to lock the rivet in position and seal the circular openings in the sheets.