Diver down flag. A diver down flag, or scuba flag, is a flag used on the water to indicate that there is a diver below. Two styles of flag are in use. Internationally, the code flag alfa/alpha, which is white and blue, is used to signal that the vessel has a diver down and other vessels should keep well clear at slow speed.
Familiarize yourself with some friendly network cables and take a closer look at common types of network media, including twisted-pair cable, coaxial cable, fiber-optic cable, and wireless.
Tevelec provides the highest quality and the full spectrum of Fiber Optic Cable types. There are three basic kinds of fiber optic cables: 1  Plastic fiber, of which the most common is for high-end audio and is called Toslink.  Then we have Multimode fiber. This is made of glass and can come in various diameters.