The Square D Homeline Plug-on Neutral Surge Protective Device (SPD) is a compact and affordable surge suppressor designed for installation into Square D Homeline Plug-on Neutral residential load centers and CSED devices. This device reduces surges that might otherwise overwhelm plug strips and damage connected household equipment. It also provides surge suppression for important items that are not compatible with plug strips such as washers, dryers, refrigerators, stoves and lighting. It is estimated, that modern homes have up to $15,000 worth of electronics and may experience up to 100 surges per month that can degrade or damage your electronics shortening their life. Enjoy piece of mind, while saving time and money on installation with the industry's easiest to install whole home Surge Protective Device. Homeline Load center Plug-on Neutral SPDs.