OnFILTER: EMI Filters for Power Lines and Ground OnFILTER offers EMI filters for real-life installations. Whenever EMI is a problem, simply plugging in our filters between power line and your equipment reduces unacceptable noise down to harmless and barely noticeable signal. Your equipment most likely already has a filter, perhaps several. Why then you ended up here? Most conventional filters are designed to help equipment to pass artificial EMC regulations having little to do with the "real world" - see this article: https://docs.wixstatic.com/ugd/53be97_d0c821427f154f3da0bec636513c99f8.pdf Often, conventional filters amplify EMI instead of suppressing it. OnFILTER' solutions work where you need them - in actual installations providing much needed attenuation of EMI on AC and DC power lines, ground, servo and VFD motors and data.