Plate Ring Single (Pyroid, 9mm, MA+MR) from Parts of Four. MA: Matte Sterling Silver. Sanded at 320 grit MR: Matte Brass. Matte Brass Dimensions: Ring Face/Top (WxL): 9 mm × 25 mm Weight: 37 grams (size 9) Composition: Matte sterling silver; Matte Brass Made in Bali SKU: 914-4-MA+MR