Tube outside diameter:4mm , 6mm , 8mm , 10mm , 12mm; Touch tubes are more flexible than nylon tubes, and feature rubber-like elasticity, a minimal radius of curvature plus superior fatigue strength. High oil resistance makes the touch tubes applicable with spindle oil, machine oil or other oils. ;Abrasion resistance:Superior mechanical strength and excellent abrasive resistance. It is most suitable for the facilities plumbing and the robot plumbing. Touch tubes are available in an extended range of colors,including black, white, yellow, red, green, blue, light green and transparent.