Only after watching a video from a different supplier of the same/similar product that I found out that when twisting the fitting onto the hose, you do not turn it the way you would when tightening a bolt - the threads are reversed so that when you tighten the other side of the fitting, the entire coupler & hose is pulled together.Some instructions would have been nice as I had written a scathing review on this product only to later find out when shopping for a replacement that the way i was twisting the coupler/hose was incorrect.Now I'm happy and can't wait to get my fuel system assembled for my 72 beetle.UPDATE:This kit went together easily and adapted to other AN fitting superbly. They connect tightly to my Weber 48IDA's and Holley pressure regulator with zero leaks. Much easier than I thought and I'm very pleased with the amount of fuel line it came with. It was enough to run from my fuel pump under the tank back to the engine compartment. Would definitely buy again - great value.