[Richard]

It’s too late for you, sorry, but this may help others in the future. Just Saturday, I had the opportunity to help @"RussWhite" with a air brake air line issue. When I first removed the line, I saw the exact fittings as in your picture, and I thought it was a custom made deal. Cutting to the chase scene, we ended up at a TruckPro parts place. The guy took one look at it and said how many do you need and what length? 16 dollars for the premade replacement.