I needed to buy an industrial type pneumatic quick release coupler. At the big box store there were two materials: brass and steel, both comparable in price. Is there a "when and where" you should use one or the other? Please educate me, otherwise I'd just go with the cheapest or brass because it's pretty. Finally getting around to asking this. Before I've just gotten the cheapest without thinking there could be an application where one is indicated and the other maybe NOT indicated. Thanks for any input.