I installed my duo 3/8 inch stainless steel hard lines today. I wish I could have got them straiter but could not see spending a minimum of 80 bucks for a tool that would get used once. I’m hoping I can find someone with a Flairing tool that will do stainless, I don’t want to buy that tool. That one is for function and not aesthetics. The curves are not quite how I drew them up in my brain but will work fine. The reason for two lines in one is for a return line, as I’m going to fuel inject the motor.