All attachments are designed to fit into our modular rails; modular rails are sold separately on our website The Bottle Holder Attachment for the Modular Storage System allows you to easily store any bottle-shaped object on the rail. We offer bottle holder diameters of 2”, 2.5”, 3”, and 4”. One order includes a set of two bottle holders that hold two bottles. ____________________________________________________________________ Features: Number of holders that can fit per rail:4 - 2” holders per rail4 - 2.5” holders per rail3 - 3” holders per rail3 - 4” holders per rail Strong & Durable Build: Rust-Proof Available in Multiple Color Options Does Not Include Bottles or Modular Rail Proudly Designed and Made in the USA by Pesca Innovations This product includes a 1-Year Limited Manufacturer’s Warranty covering defects in materials and workmanship. Warranty Page