Material: ABS Size: 9.2*4.1*3cm/3.62*1.61*1.18in (The range of glasses leg adaptation: the height of the glasses leg is greater than 7mm/0.28in, the thickness is greater than 3mm/0.12in). Note: The helmet bracket does not come with adhesive backing, so you need to buy strong adhesive yourself, preferably AB adhesive ! Color: As shown in the figure Product features: 1. Easy Installation: Can be easily installed on cycling glasses or helmets without complex installation steps, which is convenient and fast. 2. Safe and Reliable: 360-degree adjustable, can observe the rear road conditions at any time, improving cycling safety. 3. High Definition: Using high-definition lens design, it can clearly observe the rear situation without blurring or distortion. 4. Super Lightweight and Portable: The weight is only 15 grams, which will not cause extra weight burden to the rider, and it is very convenient to carry. 5. Multiple Uses: Not only suitable for cycling glasses, but also can be installed on helmets, more flexible and versatile, to meet different cycling needs. Package includes: 1 pc Rearview mirror 1 pc Helmet bracket