Product Code:SAE AS4389 Title:Nut - Self-Locking Clinch, Serrated Shank, Hole Preparation, Installation and Removal Procedures Issuing Committee:E-25 General Standards For Aerospace And Propulsion Systems Scope:This SAE Aerospace Standard (AS) provides minimum design, hole preparation, installation and removal requirements for AS3272, AS3273, MA3274, and MA3275 serrated shank self-locking clinch nuts. This standard is applicable when specified on engineering drawings or in procurement documents.