This adapter allows you to installtwo water bottle cages at the same time.It is very easy to install, suitable for most bicycle types. Features: Can be mounted with two water bottle cages at the same time. Made from aluminum alloy, rigid and durable. Integrally forging and CNC machining for added strength. Rear mounted design offers aerodynamic benefits and quick access to water bottles during racing. Compatible with most saddle types, easy to install. Specifications: Material: Aluminum alloy Dimension: 135 * 38 * 80mm / 5.3 * 1.5 * 3.1in Weight: 99g / 3.5oz Package Size: 160 * 90 * 58mm / 6.3 * 3.5 * 2.3in Package Weight: 152g / 5.4oz Package List: 1 * Bottle Cage Adapter 8 * M5x12mm Screw 2 * M5x8mm Screw 2 * Fixing Band 4 * Fixing Clip