Features: The ball socket diameter is 17mm, and the screw is standard 1/4-20, widely used in cameras, camera stands, phone stands, tripods, live streaming stands and more. Plastic, this adapter is lightweight and easy to use for long time. Great solution for adding a ball stand system to cameras or small electronic devices, suitable for car mounts, live streaming stands, desktop stands, and more. Thick and durability lock cover, butterfly shaped lock lid, easy to grip and tighten, less prone to breakage. Very suitable for installing portable displays, desktops, phone stands, cameras, action cameras, and networking cameras on existing ballhead installation systems in car/trucks or on light/microphones stands. Specifications: Material: Plastic Color: Black Size: Plastic part 3x3cm/1.18x1.18inch Package Includes: 1 Piece 17mm Ball Head to 1/4 Screw Adapter note: Please allow 1-2cm errors due to manual measurement. Please allow for slight color differences due to different display resolution.