Most C9 LED replacement bulbs use an intermediate Edison screw (E17) base and are described as compatible with standard C9 string sockets.
Brightness varies by model; listed lumen outputs across items include about 25 lumens, 105 lumens, and 120 lumens.
Listed lifetimes vary widely. Examples from listings include multi-year estimates (e.g., 3.4 years and 4.5 years) and hour-based ratings such as 3,500 hours, 30,000 hours, and 40,000 hours. Check the specific product listing for the exact rated life.
Many C9 LED bulbs are made from plastic (often polycarbonate) and are described as durable, shatterproof or non-glass, impact-resistant, and cool-to-the-touch.
C9 replacement bulbs are consistently listed at about 3 inches tall and roughly 1-1/4 inches wide (overall length commonly shown as 3 inches).
Multiple listings show safety/compliance marks such as UL Listed, and at least one mentions Energy Star. Listings commonly note features like no mercury and cool-to-the-touch or non-glass construction.
Pack sizes shown include 25-count packs, 50-count sets (often two 25-count strings), and large bulk packs such as 500. Color options include single-color blue bulbs as well as multi-color sets (for example red/white/blue or other multicolored combinations).
C9 string sets commonly use about 8-inch bulb spacing, with a lighted length around 16 feet and a total length near 17 feet. Sets often include clips on each bulb, spare/replacement bulbs or fuses, rectifiers to steady the strand, and end-to-end connectors for linking multiple sets.
