Electrical Management System (EMS) helps to protect your RV against voltage fluctuations, power surges and incorrectly wired shore power which can cause severe and costly damage to RV appliances and electronics. Improved design features include: state-of-the-art microprocessors, all weather shield assembly, rugged pull handle, secure locking bracket, built-in scrolling digital display and a tough Lean ® housing. Sleek, compact, portable design makes this unit easy to use and store. All weather shield provides additional protection while the unit is plugged in. Plug-and-play application, no installation required. Designed for recreational vehicle use only.