Manfrotto 118 Adaptor Spigot Male 16mm Short with 1/4 and 3/8 Screw

The Avenger F831TH Baby Female Swivel with Ball can convert an arm or dowel up to 16mm (5/8″) in diameter into a boom arm. It can add versatility to your non-swivelling light fixture (with optional #013) to make it more versatile. Each end has a locking Baby 16mm (5/8″) receiver. The ball joint has a pull-and-lock aluminium alloy handle with anti-rotation springs. It weighs 0.8 kg (1.76 lb).

28mm male adapter.

16mm female adapter.