Jadkinsta Tough-Claw Mount with Double Socket Arm and Round AMPS Base Adapter for 1 Inch Mount Gadgets Extension Arm 1 inch ballhead supply in this link. Specifications: Double socket arm: 1 inch ball mount on both ends The socket allows for perfect viewing angles Aluminum shell + plastic knob Length: 6cm 9cm 15cm Weight: 90g (60cm), 135g(9cm), 190g(15cm) Ball mount clamp: Plastic material: With 1 inch rubber ball head Bicycle handlebar clamp mount, open max 55mm, clamping size 16-55mm Tough Claw has a small compact design Works on round, square, odd shaped rails and bars Rubber pads provide stable, even gripping and protection of mounting surface Kindly noted: If all three items connected together, total length is around 29cm. Package include: 1 x Ball mount clamp 1 x Double socket arm 1 x Square base to ball head holder