143CA heavy duty cutting attachments are machined from high quality die-forged brass for durability and stainless steel components. Featuring drop-in tube mixer design, 143CA can be used with acetylene, propane, MAPP, propylene, fuel gas and natural gas (2 PSIG & above). Its stainless steel tubes are for strength & long life and the stainless steel oxygen lever for durability. Spiral mixer gives optimum mix of fuel & oxygen, and brass coupling nut and double O-ring seal gives a quick, hand tight, & leak-free operation.