Multi Bulb / Green Wire --For indoor and outdoor use --Features: --Improved fuse plug -- . Steady burning or flashing -- . If one bulb burns out, others remain lit -- . Extra fuse included -- . Connects at both ends. -- . To function properly, all bulbs is loose or removed from the shoket, the set will not light. --Each bulbs, except the clear flasher bulb (red-tipped) contains a shunting device designed to keep the set, operating if one or more bulbs burn out. --To make this set a flashing set, replace a regular bulb with a red-tipped bulbs. --When a bulb eventually burns out, it should be replaced immediately to of overheating. --Broken bulbs do not make contact. A broken bulb must be replaced for the set to light. --Tree lighting recommendations:--3'........100 lights, 5'........ 300 lights, 7'........600 lights 4'.........200 lights, 6.......400 lights, 8'........800 lightsAll CVS Pharmacy product are satisfaction guaranteed or your money back. --UL Certified --Made in Cambodia