Firefly Smooth Glowing Dong 5 inches by NS Novelties. Playful and body safe Thermoplastic Elastomers TPE, Firefly Smooth Glowing dongs will illuminate all your under the covers fun! Available in three bright colors and assorted graduated sizes, these glowing tapered dongs will turn you on when the lights are off. Product dimensions 5.69 inches by 1.1 inches by 2.3 inches. Package dimensions 8.8 inches by 4.3 inches by 1.3 inches. Package weight 4.90 ounces. Product material Thermoplastic Elastomers TPE.