Ercole M11-003 Hex Stud Steel 1/4″-20 & 3/8″-16 female threads

Avenger F831TH Adaptor Baby Swivelling.

The AvengerF831 Baby Female Swivel with Ball can convert an arm or dowel up to 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 5/8″ (16mm) receiver. The ball joint has a pull-and-lock aluminium alloy handle with anti-rotation springs. It weighs 1.76 lb (0.8 kg).