Is Bronze or Red Brass?
How much confusion has there been with regard to this topic. When you spend a large amount of money on a valve or a fitting you don’t expect to contend with semantics. the simple fact is that most of the valves and fittings sold for boating are actually Red Brass.
The main way to tell what you are buying is to look at the material of construction and find the UNS (Unified Numbering System) number. This number provides a means of correlating many internationally used metal and alloy numbering systems.
For instance, if you look up a Groco IBV Series Inline Valve you will note that the material of construction is C83600. The chart above shows that this number falls in the Red and Leaded Red Brass Classification. Sadly enough many manufacturers will call it bronze in the description. It has been such an issue in the past that even the US Department of Commerce issued a clarification in 1937.
So what does this mean for the average boater? It is best to find authentic Bronze for your fittings below the water line, BUT, red brass is a viable substitute since is has a low amount of zinc. Just like you should do with your food -READ THE LABEL.
Tight Lines!