10BASE-FL is the most commonly used 10BASE-F specification of Ethernet over optical fiber. It replaces the original FOIRL specification, but retains compatibility with FOIRL-based equipment. Maximum segment length values 2000 meters (This length is from node to hub.) Mixing it with FOIRL equipment, maximum segment length reduces to FOIRL's 1000 meters.

The 10BASE-FL standard requires a duplex 62.5/125 µm fiber optic cable for each link. Transmission distances of up to 2 km are possible — as is full-duplex operation

In 10BASE-F standard, the 10 represents its maximum throughput of 10 Mbit/s, BASE indicates its use of baseband transmission, and F indicates that it relies on medium of fiber-optic cable. In fact, there are at least three different kinds of 10BASE-F. All require two strands of multimode fiber. One strand is used for data transmission and one strand is used for reception, making 10BASE-F a full-duplex technology.