Most of the air lines I've seen for tractor trailers are 1/2" NPT on the ends and 1/2" ID hose. And they're generally very good quality, and should meet SAE standards if they're used for brakes. That's more than you can say of the typical air hose at your big box store. Of course, I haven't worked in a heavy duty truck plant in 25 years, maybe sizes have changed. But looking at the aftermarket sites, it doesn't appear to be the case. Most of the stuff offered appears to be 1/2".
However, the 1/2" ones I've seen and held wouldn't be very convenient for what I consider benchtop use. They're heavy and bulky. But I'm one of those people that tends to despise coiled hoses in general. I'd much rather have a reel over the bench (actually over my head so it's mostly out of the way of stuff on the bench), or short hoses with a manifold within hands reach (under the front or side lip of the bench).
I've ordered all of my recent hoses from McMaster-Carr. The turnaround time is very quick, the pricing and shipping is quite reasonable, and they'll put together most typical configurations in any length you need. All of the hoses I have in active use in sub-50' lengths are from McMaster-Carr.
Do you really want a coiled hose, or do you want a self-retracting reel?
