A longitudinal stop-coil, for reducing induced main-frequency hum in medium-length co-axial circuits, such as video feeds. This is a portable design, housed in a standard Canford extruded box with protective ABS bezels, for life in the tool-kit ready for trouble-shooting. Alternatively it may be fixed to a flat surface using an Extruded-box mounting kit, stock code 16-722. It offers electrical performance equivalent to that of the earlier BBC-designed Longitudinal Stop Coil CH43, but at a lower price and weight. Connectors are BNC. Dimensions: 93(w) ×107(d) ×55(h) mm (over bezels).