An electrical component testing device comprising a housing having at least one recess covered by a flexible membrane so as to form a chamber. Electrical therapeutic energy is delivered to a nerve branch of a renal artery of the patient, thereby treating the chronic hypertension. The crane has an electronic control device with a computing device and with a display. Anti-flutter filtering may help reduce display flicker due to the interlaced nature of television displays. The invention also relates to the use of said shell body to produce rotationally symmetric andor not rotationally symmetric shell-shaped components.