No, these plugs aren’t oily, but they do look like drops of shimmering oil. The double flare plugs have a round shape and blueish color, but reflect a rainbow of tones in the light. Due to the nature of the material, each and every plug is unique, but we’ll do our best to provide you with a matching set since they’re sold in pairs. Keep in mind also that sizes 12G - 00G have an 8mm wearable area, sizes 1/2" - 24mm have a 10mm wearable area, and sizes 26mm - 30mm have a 12mm wearable area. The Oil Slick Glass Plugs are available in any of the following sizes: 12 gauge (2mm), 10 gauge (2.5mm), 8 gauge (3.2mm), 6 gauge (4mm), 4 gauge (5mm), 2 gauge (6mm), 0 gauge (8mm), 00 gauge (10mm), 1/2 inch (12mm), 9/16 inch (14mm), 5/8 inch (16mm), 3/4 inch (19mm), 7/8 inch (22mm), 1 inch (25mm), 1 & 1/8 inch (28mm), 1 & 1/4 inch (32mm).