So you need a ball valve. Are there any differences between the 304 vs 316 stainless steel?
If so, why do they matter?
The simple answer is yes, these types of steel function differently.
And yes, they definitely matter if you are concerned about corrosion.
Stainless steel parts contain at least 50% iron and 10% chromium.
Generally speaking, the more chromium, the greater the corrosion resistance.
Stainless steel 304 resists corrosion fairly well, in part, because of the addition of nickel to the steel. However, in some instances, SS304 might not fill the bill.
Stainless steel 316 parts have higher percentages of nickel and the addition of molybdenum - both work with the chromium to make it more resistant to chlorides. They are among the most resistant to corrosion you can find among standard stainless steels.
This is why you see SS316 parts used when the part will be exposed to corrosive chemicals such as in a marine environment or the petroleum industry.
While you can use stainless steel 304 vs 316, the SS316 parts are made to last longer in adverse conditions. Staineless Steel 304 parts cost less, but may have a shorter lifespan in some conditions.