The Schneider Electric VW3A58405 is an RFI input filter, Size 5, designed for use with Altivar variable speed drives to attenuate conducted electromagnetic interference back onto the line side. It's a panel-mount filter that installs between the supply and the drive input.
As a Size 5 filter, it's sized for the corresponding Altivar drive frame. Mount it close to the drive input to keep the cable run between filter and drive short — long pigtails between the filter output and the drive input defeat the common-mode attenuation the filter provides.