Black Plated Hinged Segment Rings. The hinge on this specific design allows the wearer to never lose a small segment piece again and it has that easy snap seamless fit. Sold as individuals, not in pairs. Can be worn in lobe, cartilage, septum & daith piercings. Made entirely from Surgical Steel. Material: 316L Steel Size: 18g 3/8" (1mm 10mm) 316L GRADE SURGICAL STEEL316L surgical steel is one of the most common materials used for body piercing in the United States and is considered implant grade It is a man-made material that is made by mixing iron with other metals to achieve greater strength.The alloying process involves melting various metals together, in order to produce a "new" metal. Depending on the specific recipe used, each variety of steel gets a grade designation. It is a strong and durable metal that is very easy to clean, which is important for body piercings - especially new ones. It is also corrosion-resistant so it won’t rust or tarnish. Polishing the steel to a mirror finish results in a protective layer of chromium oxide that helps keep the nickel content trapped inside. There is a risk for people with extreme nickel allergies, in which case, titanium should be used.