Solar Flash keychain: (ideal for advance promotional gifts) 1: Solar powered keychain, no battery required. 2: Automatic flash when have lights, and running forever. 3: Ultra Slim Compact Design 4: really waterproof gifts ***Put your logo inside the keychain and flash forever. ***Many size for choosing. We can do any size Solar Key Chain for you! SIZE36*19*8.3MM SIZE41*18*8MM SIZE50*25*8MM SIZE50*25*8MM SIZE60*25*8MM