Transient voltage surge suppressor (TVSS) units protect sensitive electronic equipment from transients. TVSS is a modular parallel device designed for service entrance, distribution or branch panel applications. This kit is a digital display unit and counter. It is for three phase I-Line Plug-on SPDs. The unit has a horizontal orientation with the RJ45 patch cable connection at the bottom of the unit. This display unit is a replacement for TVSS Surgelogic.