Our standard three-phase sine filters for frequency converters are manufactured in aluminum boxes with a heat sink (2.5 - 75 A), where the filter is filled with a special material or as a tightening structure (32 - 2000 A), which are protected from adverse environmental influences by impregnation. Compared to cable ties, the filters in the boxes are designed for a lower inverter switching frequency, but are characterized by a higher voltage drop.