The WGF-12 accepts up to twelve pre-terminated fiber optic cables with attached connectors. It is designed to provide a means of bringing fiber optic cables into a shielded enclosure while maintaining the enclosure's radio frequency isolation integrity. The filter has a patented removable center plug, which is surrounded by twelve waveguide bores. When the center plug is removed, connectorized fiber optic cables can be inserted into the peripheral cable sized slots.