Semi Rigid Nylon Tubing is light, about 1/9th the weight of similar sized copper tubing, resistant to a wide range of chemicals and is suited to applications such as fuel lines, oil lines, petrol tank breather pipes, greasing sheaths, pneumatic controls, bleed lines etc. It has many other uses outside the pipe application business. We have customers that have used it flat on to behave as a shock absorber at the back of filling cabinet drawers!! Also we have seen it used inside wind socks to add stiffness.
Fittings are usually put on the outside of this product so the outside diameter (OD) is the important measurement when using for example push on fittings