Use brass pipe-to-hose fittings above-the-waterline and not mixed with bronze fittings.The brass fittings that we offer are for above-the-waterline use only. 1/8"-3/8"dia. are yellow brass. 1/2"dia. and up are red brass. Due to the difference in nobility between brass and bronze, which can result in galvanic corrosion (and a failure of the fitting), we recommend that you not use these alloys together in saltwater environments. For reasons of safety, we suggest the use of cast bronze or Marelon tailpieces and hose instead.NPT Pipe-to-Hose BarbThese machined brass fittings are suitable for fuel, water and other common marine fluids in above-the-waterline applications. The hose barbs are intended for use with hose clamps (sold separately). Threads are tapered "NPT", which stands for "National Pipe Thread." Sized by hose ID to various male NPT fittings.