These special sinusoidal filters for frequency converters that feature higher switching frequencies produce single-phase and three-phase capacitors and with or without. As far as mechanical parts are concerned, these filters are designed for specific applications with precisely defined conditions. They are most often placed in aluminum boxes with a cooler, where the filter is filled with a special material or as a tightening structure, which are protected from unwanted environmental influences by impregnation. Compared to cable ties, the filters in the boxes are dimensioned for a lower inverter switching frequency, but are characterized by a higher voltage drop.