Features: Aluminum alloy: Aluminum alloy material, it is resistant to drop and wear, and can bear harsh outdoor environment. Simple and stable: 1in ball head 25mm, with three rubber circlets(10/12/14mm), can accommodate circular rod with diameters of 0.39inches (10mm), 0.47inches (12mm), 0.55inches (14mm), 0.63inches (16mm). Simple locking mechanism: The unique locking design ensures that the device remain stable and not easily shake while driving. Suitable for multiple devices: compatibility with most smartphones, sports cameras, and other devices to meet the needs of different users. Easy to install: It can be easily installed on the motorcycle rearview mirror without the need for additional tools, making it easy to get started. Specifications: Material: Aluminum alloy Size: 25mm Ballhead Package Includes: 1 Piece 25mm Ballhead Mount Base note: Please allow 1-2cm errors due to manual measurement. Please allow for slight color differences due to different display resolution.