100 multicolored christmas lights

Many listings note that if one bulb fails the rest of the string stays lit. Several sets also include replacement bulbs and spare fuses, and some use lamp-lock or similar features to keep bulbs secure and easily replaceable.

Lighted lengths in the sample listings range from very short decorative strands (around 5.5 feet) up to long runs (examples include 50 feet, 66 feet, and 100 feet on spool/strand). Reported bulb spacing includes about 2.5 inches, 3 inches, 4 inches, 6 inches, and 8 inches, depending on the style.

Multiple listings state UL certification or UL listing for indoor and/or outdoor use. Descriptions may note UL‑certified cords or sockets and approval for indoor/outdoor decorating.