Most consumer devices ( modems, routers, switches, laptops, etc ) do NOT properly ground network cables. This handy adapter fixes that problem with ease. Simply plug 2 shielded cables into it, and it will properly ground each cable, providing the protection you need around your work place and any other area where you spend much time or are in close proximity to the network cable. Laptop computers are almost always ungrounded. When the laptop is plugged-in to the charger, and the laptop user is nearby or touching the computer - the user is being greatly exposed to high-frequency current. This has been measured in the lab. When a laptop is grounded through its ethernet port with this adapter, it greatly reduces this current. The most recent test showed a nearly 98% reduction in current traveling through the human body as soon as the ElectraHealth Ethernet Grounding Adapter was plugged-in.