727 cooler line fitting size

I found it on Summits website. I ordered 1" which when I measured up my -6PTFE tubing it would fit. Im not sure if you are using regular braided, if so it may have a larger diameter. The next size up is 1.25". If you have the tubing in hand just measure across 2 tubes side by side. Here is a link

http://www.summitracing.com/parts/dei-010419/overview/