These classic black plugs have single flares and are smooth and shiny. The visible parts of each plug are black, though the remainder is clear since they’re made of glass. They’re sold in pairs, though each plug may be slightly different due to the nature of the material.We’ll do our best to provide you with a matching pair, though. Get your Single Flare Black Glass Plugs in any of the following sizes: 16G (1.2mm), 14G (1.6mm), 12G (2mm), 10G (2.5mm), 8 gauge (3.2mm), 6 gauge (4mm), 4 gauge (5mm), 2 gauge (6mm), 1. gauge (7mm), 0 gauge (8mm), 9mm, 00 gauge (10mm), 1/2 inch (12mm), 9/16 inch (14mm), 5/8 inch (16mm), 3/4 inch (19mm), 7/8" (22mm), 23mm, 15/16" (24mm), and 1" (25mm). Full length ranges from 15mm - 20mm and the wearable surface ranges from 10mm - 11mm. Note how the "O" ring makes the wearable surface adjustable.