316L steel, or surgical steel as it is also called, is the material that most of our jewelry is made of. It contains about 17% chromium, 12% nickel and 2.2% molybdenum, but it is so tightly bound in the metal that less than 0.1 millionth of a gram of nickel is released per cm2 and week. It is so little that 316L passes the EU directive for products that come into close and long-term contact with the skin. The limit value is 0.5 millionths of a gram/cm2/week. "Normal" nickel allergy sufferers usually cope with the steel just fine, but if you are very sensitive or worried, you can choose titanium instead.