4mm (0.16") Inner Diameter Silicone Vacuum Hose by Foot (Black) Universal Application for All Air/ Pump/ Gauge/ Turbo/ Vacuum Fittings Inner Diameter: 4.00 mm (0.16") / Outer Diameter: 8.00 mm (0.315") Withstands Operating Temperatures from -40 F to +428 F Degrees Fahrenheit (-40C to 220C Degrees) Made of 100% High Quality Silicone Material Tubing Maximized Resistance to Heat and Corrosion