Features and Benefits:

• Sunex 310EPC 3/8-Inch Drive 5/16-Inch Female Pipe Plug Socket
• No doubt, the strongest impact socket line around. Sunex Tools impact sockets tackle the toughest jobs with a chrome molybdenum alloy steel grip that won't let go. With solid durability that keeps them driving through job after job, we've got sizes and styles enough to fulfill any need.
• Forged from the finest chrome molybdenum alloy steel-the best choice for strength and durability
• Radius corner design extends the life of fasteners, design drives the side of the fastener instead of the corner
• Socket is black oxide finish and has etchings for identification

This is a female pipe plug socket. It is 5/16 in. and 3/8 in. drive. This socket is designed to tackle the toughest jobs with solid durability and keeps them pounding job after job.