Shielded housing for 2 HV-LISN, 2 paths with cable feed throughs for HV+ and HV-, shield can be connected to the housing, 2 measurement ports N, 1 monitor port N, with connecting cables between inside measurement ports and outside N-connectors. All models of the NNHV- and NNBM-series can be inserted. For full CISPR 25 Ed. 4 compliance a modification of the back side circuitry of the NNBM series is required