Profile: Hotstick USA, Inc. offers high sensitivity voltage detector for emergency responders. The AC HotStick™ is a safety device designed for professional rescuers which provides warning of exposed high voltage AC from a safe distance. It gives early audible ("beeping") and visual (flashing LED) warning of the presence of dangerous voltages without the need to contact the surface carrying the current. The closer the user comes to the source of the voltage, the more rapidly the unit beeps and flashes.