Surgical Stainless Ring (Ring) #11. ⚪︎ The inner diameter of the #11 ring, measured with a ruler, is approximately 16.33mm. Inner diameter: 16.33mm Inner circumference: 51.31mm Width: 7mm ⚪︎ Stainless steel with excellent properties such as rust resistance and resistance to corrosion, oxidation, and heat. ⚪︎ Called "316L" under JIS standards, it is a material with extremely low allergenicity among stainless steels (also used in medical tools, etc.) ⚪︎ Surgical stainless steel, with its high hardness, is resistant to scratches, and one of its attractions is that the metallic luster is maintained without dulling. Shipping will be done anonymously via Nekopos. 428-210