I bought this product for outdoor use around my upstairs window, facing the street. My neighbors have been adding more lights the past few Christmas holidays and I felt I should make my contribution. I'll try to make my description a technical one, to give the best overall view of the product.
The lights are about average in brightness and come in four colors: red, amber, green, and blue. The bulb portion is roughly cone-shaped and about one inch long. The bulbs are textured to produce variation in brightness depending on the viewing angle, a kind of glittering effect. Each bulb is an LED, which are polarized. This means the connections have both a positive and negative terminal. If reversed, the bulb won't work. For this reason, the sockets for the bulbs are "key-shaped" so that the bulbs will only easily insert in the correct orientation. I received two spare bulbs, red and amber.
One or two reviewers commented on dead strings. I suspect a forcibly reversed bulb might be involved. Not wanting to damage my string, I am reluctant to test this theory.
Each bulb is spaced at about four inch intervals and connected to it's neighbors by four green wires; a bundle about the diameter of a pencil. As a result, the string is fairly stiff and heavy. The coiling forces cause the string to twist slightly so that the bulbs tend to face alternating directions. Picture a zig-zag stitch. The coiling forces tend to frustrate any attempt to point the lights in a specific direction. For the use of decorating a tree or outside window this causes no problems since the light is well dispersed. In conclusion, I will simply say that the lights worked perfectly for me and looked quite pretty.