Specification:Product name: Copper Brass Square Keychain LanternMaterial: CopperKeychain size: 32mm x 8mm(length x width)Weight: 8.4gTritium Vials Size: 3x22.5mmTritium Vials Color: green、blue、white、orangeFeatures:1.It is a keychain fob specifically designed to hold a standard 3x22.5mm self-luminous tritium vial.2.Tritium vials come in a variety of colors、 and will glow for many years without requiring any type of "charging" from sunlight.3.The light never needs batteries、 and is really only visible as a glow in low light conditions inside about 30 feet. Pretty much its just a cool way to accessorize your stuff.Package included:1 x Copper Brass Square Keychain Lantern