Stainless Steel Hollow Tunnel Ring of Gems Ear Expander Ear Plugs Rose gold plated surgical grade stainless steel. Comes in sizes 12g, 10g, 8g, 6g, 4g, 2g, 0g, 00g, 7/16", 1/2", 9/16", 5/8", 3/4", and 1". Hollow tunnel or hollow post design. Channel of Cubic Zirconia gemstones.