This can be used for the common umbrella adapters, swivel brackets, and other lighting clamps and adapters.

The diameter fits the standard 5 ⁄ 8 inch (nominal) hole found on many of the lighting accessories cited above.

One end has a 1 ⁄ 4 inch X 20 threaded stud.  The other end has a 3 ⁄ 8 inch X 16 threaded stud.

The 1 ⁄ 4 inch threaded stud can be used to attach many flash hotshoe ⁄ shoe adapters that have a threaded 1 ⁄ 4 inch - 20 hole on the bottom.

Price: $4.00 + shipping