Features: Make of Aluminum, ensuring durability and long terms use. The 3/5/7/9/11/13 slot structure provide more attachments point for various accessories. Light weight design that doesn't create excesses weight. Specifically designs as accessories for camping lights, enhancing functionality. Easy Installation: Can quickly installed on camping lights without tool or skills. Specifications: Materials: Aluminum Style: 3 slot/5 slot/7 slot/9 slot/11 slot/13 slot 3 slot size: about 2.1x3.50cm/0.83x1.38inch 5 slot size: about 2.1x5.50cm/0.83x2.17inch 7 slot size: about 2.1x7.50cm/0.83x2.95inch 9-slot size: about 2.1x9.50cm/0.83x3.74inch 11 slot size: about 2.1x11.50cm/0.83x4.53inch 13 slot size: about 2.1x13.50cm/0.83x5.31inch Package Includes: 1set Aluminum Rail note: Please allow 1-2cm errors due to manual measurement, make surely that you not mind before order. Due to difference between different monitors, the picture may not reflect the actual color.