F-tone small form-factor (SFF) is a compact optical transceiver used in optical communications for both telecommunication and data communications applications. It is a popular industry format supported by several fiber optic component vendors. SFF transceivers are designed to support SONET/SDH, Gigabit Ethernet, Fibre Channel, and other communications standards. SFF transceivers are available with a variety of different transmitter and receiver types, allowing users to select the appropriate transceiver for each link to provide the required optical reach over the available optical fiber type (e.g. multi-mode fiber or single-mode fiber). Optical SFF modules are commonly available in four different categories: 850 nm (SX), 1310 nm (LX), 1550 nm (ZX), CWDM, WDM/BiDi versions, compliant with STM-1/OC-3, STM-4/OC-12, and STM-16/OC-48, 100BASE & 1000BASE, Fibre Channel 4x/2x/1x, 18-wavelength CWDM Transceiver Compliant with ITU-T G.694.2. RoHS Compliant. MSA: