At TIONEER, we use surgical grade stainless steel for our massive selection of metal jewelry. Surgical grade stainless steel is abundant in our collection due to its hard body, incredible resistance to corrosion and tarnish. Stainless Steel Letter E Initial 3D Monogram Engraved Square Flat Top Biker Style Polished Signet RingSurgical Grade Stainless SteelEngraved Letter E Initial 3D Monogram Engraved DesignTop Dimension: 13mm x 13mm (0.51 inch x 0.51 inch)Standard Fit WearMinimalist Style Polish Finish