The 320 UnderBridge system is a hardwired fail-safe communication system designed specifically for underbridge access equipment platforms and bridge inspection trucks operations. It provides a safer working environment for all workers while operations are being directed. The system consists of a Master Unit and 3 remote units. Built using the latest technology, remote units use high-impact nylon plastic materials, and the master unit electronics are enclosed in a heavy-duty nylon enclosure. Please note this is a 320 Underbridge Master Unit only.