Tour Guide System
http://www.meicheng.com.tw/english/language/TOUR_GUIDE_SYSTEM.html
Tour guide system WT-480T / R is a UHF wireless tour guide system which performs better signal quality to get low s / n radio (signal noise) than VHF does. The WT-480R receiver has a hang-type earphone, simultaneously transferring 16 selectable channels and 6 channels parallel without interference. This system includes rechargeable batteries. Simply plug in the charger directly (HDC-30, HDC-202) for a long time use.
