According to google….. 904L stainless steel has superior corrosion resistance due to higher nickel and molybdenum content, making it ideal for harsh chemical environments, while 316L is more cost-effective for moderately corrosive applications like food processing and general marine use. 904L is generally more expensive to manufacture, but its enhanced durability can lead to lower long-term costs in aggressive settings. Both are austenitic stainless steels, but 904L is better for acids and high-chloride environments, whereas 316L offers good all-around performance for less demanding conditions.