Perfect for safely troubleshooting and testing audio systems. Offers an output range of 0-8 volts at a variable 13 to 10,000Hz tone for setting system levels, checking speaker x-over points, verifying connections and general trouble shooting. The TL-PTG2 also has a 9v speaker popper for visually testing speaker connection polarity. Connections can be made via supplied RCA or alligator clips. It features an auto shutoff for extended battery life. It is a very small size, making it easy for hand held use and is also designed with rotary control knobs for easy tone and level adjustments.