Review on 🔧 Brass Transmission Line Fitting: Derale 13031 5/16" Cooler Line to 3/8" NPT Hose Barb - Universal by Chris Reddick

This is a good quality solid brass fitting, assembled as intended. I bought mine to connect my existing 5/16" steel transmission coolant lines to a 3/8" flex hose when installing a new offline transmission cooler ahead of the radiator/condenser. This isn't a common size combination, so it was helpful to find everything together here. If you have a well-stocked hardware store near you, you can assemble all 4 matching parts for this kit separately to save a lot of money. TIP 1: Use pipe sealant or Teflon tape on the NPT threads (where the barbed back end is on the compression fitting), but DO NOT use pipe sealant or tape on the compressed side of the fitting. I've read online and seen MANY warnings on YouTube videos not to use teflon tape on compression fittings, but they ONLY talk about the compression fitting side of this product. TIP 2: Use good quality wrenches when installing. It's brass, and brass is soft; If you use the wrong tools you will damage it. Use good adjustable wrenches (remember these are standard wrenches, not metric!)