304 is a stainless steel grade, and a maker who states it is telling you the fitting is not plated zinc. In a room that is wet twice a day, that is the distinction that decides whether a towel rail still looks like itself in three years.
Why the grade is stated at all
Stainless steels differ in how much chromium and nickel they contain, and that is what resists corrosion. 304 is the common architectural grade, sometimes written 18/8. 201 appears on cheaper fittings, contains less nickel, and pits sooner in damp air. A listing that just says “stainless steel” has not told you which.
The alternative you are being sold against
Plated zinc alloy. It looks identical when new, costs far less, and blisters where the plating is chipped or where the fitting meets a wet surface — usually the base of a soap dispenser or the mount of a rail.
Where it matters most
Anything permanently in the splash zone: shower shelves, hooks, rail brackets, hose fittings. Anything on a dry wall away from the shower can be plated without consequence.
What it does not mean
Stainless is not stain-proof. It still shows limescale, and it still needs wiping. It simply does not corrode underneath while it does so.
Questions people actually ask
Is 316 stainless steel worth paying for in a bathroom?
316 adds molybdenum and is specified for marine and chlorinated environments — a swimming pool rather than a bathroom. In a domestic bathroom, 304 is what the fitting needs.
Why do some 304 fittings still rust?
Usually surface contamination rather than the steel itself — iron particles from cutting or from a nearby steel fixing sit on the surface and rust there. It cleans off, and it does not mean the fitting is failing.
Last reviewed 5 September 2026