Description Developed from the need to instantly identify your important bag pockets, pouches, and keyrings - The Spark helps you locate exactly what you need when you need it. The Spark is the smallest and most economical of the Glow Fobs. Purchase a 1 or 3 pack in green or blue tritium. Or purchase a highly discounted 5 pack with the following colors:  green, blue, purple, yellow, and red Buy for yourself and your family & friends around you. Features: 1 Cylindrical Tritium Lamp/unit Injection Molded Polycarbonate Casing Glass Breaker Tip Keychain Hole / Lanyard Loop Keyring Waterproof Dimensions: Length (excluding keyring): 0.825" Diameter (excluding keyring): 0.31"