The KEMA 801 is an additional decoupling network (ferrite tube clamp) for immunity test according to IEC 1000-4-6:1996 (EN 61000-4-6:1996) when using the alternative EM- clamp injection method. It shall be inserted between the EM- Clamp (KEMZ 801) and the auxiliary equipment. The KEMA 801 prevents, that the test signal applied to the EUT affects other devices, equipments or systems, which are not under test and improves the reproducibility of the test results. The clamp mechanism of the KEMA 801 makes possible a simple insertion in the test setup.