Heavy duty drop-in style, 12 unit multi-charger for Williams Sound R37, R37-8, R38, RX22-4 and R863 receivers and T46 transmitter. The CHG 3512 PRO charges Williams Sound receivers and transmitters over the course of a 16 hour time span. Helps keep FM equipment organized and saves cost on having to replace alkaline batteries. Features individual charging LED indicators. LEDs blink when batteries are fully charged.