The DataPro 1442-FF coupler is a duplex multimode fiber optic
adaptor with dual ST jacks at one end and dual SC jacks
at the other.
This coupler serves two functions: it splices two fiber cables
together, to create a single cable of combined length; at the same
time, it adapts one set of connectors to another, so mismatched
cable types can be joined together.
It has two of each connector on each side, as dual-channel fiber
is the most common way to get great performance and speed.