Review on 🔧 Efficient GM Transmission Cooling Line Die and Adapter Set: MASTERCOOL (71099-TC Silver 3/8") by Mod Kindred

I've used this on stainless steel tubing and it works. Be sure to apply enough pressure or you will deform it and the barb OD will be greater than approximately 0.010 inch which may result in the end of the hose not fitting into the fitting. Practice on some pipe scraps before using it. It depends on the pipe. Compare the result with the original sample to see how much pressure provides the right shape. If you form an oversize, it can be neatly filed down a few thousandths if you need to use it.