Firefly Halos are glow-in-the-dark cock rings made of soft and stretchy silicone for a snug and comfortable fit, ensuring prolonged performance and enhanced climax. Available in assorted colors and sizes. Collect them all! Product Dimensions: 2.1 x 2.1 x 0.4 in. Package Dimensions: 4.1 x 2.8 x 0.6 in.