Feature: 1. Wide Application: 1in ball adapter fits for 9‑15mm/0.35‑0.59in diameter rails, bikes, scooters, mobile phones, navigations, rearview mirrors, etc. 2. Premium Material: Double ball bracket is made of aluminum alloy and rubber material, wear resistant, rustproof, sturdy and durable. 3. Excellent Performance: Ball mount base can prevent loosening in high vibration, anti slip and provides a secure grip with slight flexibility. 4. Professional Design: Professional manufacturing, exquisite workmanship, weather resistant, can be used in harsh environments, stable and reliable. 5. Simple Installation: The installation is simple, M4 mounting hole, no complicated operation is required, convenient for using, save your time. Specification: Item Type: Ball Mount Base Material: Aluminum alloy, rubber Ball Head Size: Approx. 1in/25.4mm.Mounting Hole: M4 Applicable Size: Approx. 9-15mm/0.35‑0.59in rails Application: 1 inch ball bracket is suitable for 9-15mm/0.35‑0.59in diameter rail, bikes, scooters, mobile phones, navigations, rearview mirrors, mini handlebar, etc. Package List: 1 x Ball Mount Base1 x U Shaped Accessories2 x Screw2 x Nut1 x Washer1 x Hex Wrench1 x User Manual