<p>Specifications:<br> Made of CNC machined aluminum alloy, smooth surface, rust-proof and durable. <br> Suitable for handlebar diameter: 19mm-33mm or 19mm-40mm. For single screw models, only one bottle holder can be installed. <br>For twin-screw models, you can install one bottle holder in the middle, or two bottle holders on both sides, but for twin-screw models, you cannot install<br><br> Product name: Water bottle conversion seat<br> Material: Aluminum alloy<br> Model: 1: Single screw, 2: Double screw<br> Scope of application: General for bicycles, electric vehicles and motorcycles<br> General installation: seat tube/rose handlebar/straight handlebar<br> Features: lightweight, portable and durable<br> Single screw conversion seat size: 7.7cm x 4.6cm/3.03 x 1.81 inches (approx.)<br> Double screw conversion seat size: approx. 7.7cm x 5.3cm.<br> Single screw conversion seat mounting tube diameter: 19mm-33mm/0.75-1.3 inches (approx.)<br> Double screw conversion seat mounting tube diameter: 19mm-40mm/0.75-1.57 inches (approx.)<br><br> Note: Due to the light and screen setting difference, the color of the item may be slightly different from the pictures. Please allow slight size differences due to manual measurement. Package Included: 1: 1 x Screw-in Conversion Base (Bottle Holder Not Included). 1 x 2.5mm Hexagonal Socket 1 x 3.0mm Hexagonal Socket 1 x Thick Protection Washer 1 x Thin Protection Washer 2: 1 x Double Screw Conversion Base (Bottle Holder Not Included). 1 x 3.0mm Hexagonal Socket 1 x Thick Protection Washer 1 x Thin Protection Seal