Description: Expansion ball head: compatible with a variety of devices for constant use, can be charged with sports cameras or phone holder Anti Shaking: grips tightly and keeps devices stable in any terrain. Material: High-quality material, wear-resistant, sturdy and durable. Easy to install or remove. Quality: Professional production, stable performance, has a long service life. Universal: Round Ball Head Mount Suitable for Most Bicycles, Electric Vehicles, Motorcycles, etc. Specification: Material: 304 Stainless Steel Aluminum Alloy Size Chart: Screw Length: 6.5cm/2.56 inch Package Include: 1 Piece Round Ball Adapter Base Note: Please allow slight errors due to manual measurement and different monitors.