Firefly Halo 50mm e or approximately 1.96 inches Cock Ring Small Clear from NS Novelties. 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 inches by 2 inches by 0.4 inch. Product material Silicone.