Mastercool flaring tool 71475-PRC (black) is a universal kit that fabricates flares for GM fuel lines (5/16″, 3/8″); push connect ones (1/4″, 5/16″ 3/8″); metric bubble flares 4.75mm, 6mm, 8mm, 10mm; flare/double flares:(3/16″, 1/4″, 5/16″, 3/8″, 1/2″).
The kit comes in molded carrying case 15 x 10.3 x 3.2 inches, 11 pounds, 90 days limited warranty.
The Mastercool flaring tool is made to flare brake and AC lines, in there appropriate sizes. There are dies which will make the bulge in the line for the clips inside the fitting.
I mostly use the tool for making double and bubble flares on brake lines. But it is also capable for a GM fuel line applications.
It has no 37 degree flare, so you need to purchase a separate die set for stainless steel brake lines. The kit also does include the Transmission Cooling Line Die and Adapter Set for GM, but many people would not need this tooling and it keeps the price a little lower. The box has a spare area to hold them. You can purchase them separately.
Mastercool flaring tool is not cheap, but quality tools usually ARE expensive. The cheap $30 parts store flaring tool wasted too much time and tubing because sometimes the flares wouldn’t be offset a bit, cause a leak, leave one side thin, etc. I think, there’s no other tool that will allow you to flare brake lines faster than Mastercool flaring tool. With it, you will be able to do special transmission, fuel, metric, male ends of fuel quick-connect lines, and power steering flares on a bunch of different vehicles.
It takes a little bit of playing with the fittings at first but once you learn how to use the tool and different anvils and flares it works excellent. Very short learning curve, do some testing first before doing the final flare. Be careful while flaring copper alloy tubing, because when you’re doing the second step of a double flare, it’s very easy to over-compress the flare. There’s so much mechanical advantage with the hydraulic ram, it’s easy to over-do it. Once you’ve got the hang of it though, it’s great. Mastercool flaring tool is also good to use to flare lines while a line is mounted to a vehicle.
This set works flawlessly for me every time I use it, definitely recommend it! See also our best flaring tool reviews.