The 310 Series is a high quality Diversity UHF camera-mount wireless system that features 188 User-Selectable frequencies displayed on an LCD screen to assure you of always finding a "free" channel. The series consists of the 305UDR On-Camera receiver, the 35BT Belt-Pack transmitter, the 35HT Handheld microphone/transmitter and the 35XT Plug-In transmitter.