6.3mm I/D x 12.7mm O/D The hose has a fluoroelastomer inner lining that protects against petrol, oxidised petrol, ethanol extended petrol, and diesel fuel. The ingredients in the fuel we put in our cars have altered in recent years. To make the fuel cleaner and more efficient, several ethanols and oxygenators have been added. Unfortunately, these Ethanol and Oxygenator additions to petrol are chemically aggressive, and they have a tendency to enter and damage the rubber compounds utilised to create fuel hoses, \"O\" rings, and accelerator pump diaphragms in the past. Under the influence of Ethanol, these rubber components deteriorate, expand, and fracture, eventually failing to function. R9 fuel hose was developed to function with modern fuels and has less than 3% of the permittivity of fuel hose from the 1980s and 1990s. It even outperforms the \"A1\" (ISO 7840) hosing that is required for usage in the marine environment, where fire safety is extremely important! Specifications: Maximum Fuel Permeation: 15g/m²/day Temperature Range: -34°C to +135°C Working Pressure: max 100 PSI Burst Pressure: 900 PSI Min Bend Radius: 0.75\" Vacuum HG: 24\" Weight: 0.10lbs/ft