UNC Group SpeedaLite 50 (OM4) fiber optic cables are fully tested and gauranteed for the lifetime. The 50 refers to the actual diameter size of the core itself - measured in microns. OM4 cable is recommended for premise applications like backbone, horizontal and intrabuilding connections. OM4 fiber optic cable can carry a 150 Gigabit ethernet signal up to 100 meters making it a popular choice among those who require a network that can handle a large amount of data at the SpeedaLite .