Coupling. For connecting attachments directly to mounting bases. 3/8"-24 female threads on each end with 4mm set screws and allen wrench included. 18mm diameter, 51mm (2 inches) long. Type 303 stainless steel. [split] [tab1]What's Included[/tab1] [tab2]Assembly Instruction[/tab2] [tab3]Video Demonstration[/tab3] [split] [tab1contents] (1) Coupling (2) 4mm set screws (1) 2mm... View more