6,35 mm (1/4") double walled tubing EVA outer wall and an inner proprietary polymer barrier. 3mm (1/8") inner diameter and 6,35mm (1/4") outer diameter. Fits Kegland and Duotight 6,35mm products.Please Note: Sold per meter, so if you choose 2 in the select box you will get 2 meters of hose. Measurements may differ circa +/- 10mm.