What is the primary use of an electric light VDS?

The primary use of an electric light visual distress signal (VDS) is for nighttime distress signaling, specifically to convey the SOS signal. In emergency situations, the SOS signal is universally recognized as a call for help. An electric light VDS can be used effectively at night because it produces a bright, visible signal that can be seen over distances, even in low-light conditions. This makes it a critical tool for alerting other boaters, search and rescue teams, or anyone nearby that you are in distress and need assistance.

While there are other types of signaling devices for daytime use or as navigational aids, the electric light VDS is specifically designed for nighttime scenarios, which is why it is essential for boaters to have this equipment readily available during nighttime boating activities.