If your line is stainless, it's single. If it's Aluminum or steel it should be double. If it's euro style, it's bubble flare.
The inline tube and other vendor tubes are available in SS or "OEM". Either should work with whatever you are mating with.
The flare on the inlinetube.com will be according to material probably. Call or email them.
You can use any style flare with rubber hose, The flare acts like a barb. You are looking at a flare (bubble, single or double) without the nut.
These styles go by many names. SAE, ISO, American, Japanese, European, DIN, AN/JIC, JIS....so make sure you read the label. You want AMERICAN SAE 45 deg with a SAE thread callout. SS is not necessary, so get O'Reilly's steel SAE or inlinetube OEM. You don't want any MM threads. Be careful, some Metric threads seem like they fit. If your line is non magnetic it is either SS or AL. If you can scrape a burr off it with a knife, it's AL. But you should be able to tell by just looking, bending. Don't overthink it too much, just get new tube and put it on with some rubber hose here and there. Tubing doesn't care what truck it's in or what motor it goes to.
