- The P.K.E. Meter (also known as Aurascope) was one of the Ghostbusters' tools invented by Dr. Egon Spengler that enabled them to track ghosts and other entities. - GHOSTBUSTERS P.K.E. Meter features: Two button operation. Left sliver button for quick power up demo button (with auto-shut-off). Right silver button power up button (constant on, press to power off). Sequential lights and sounds. Motorized extending faux antenna with green scanning LEDs. Recessed viewing green tinted screen with green sequential lights. Five colored LED indicators (glows steady for show). Master power off slide switch located on the back bottom of handle (below the battery compartment door). Rotating belt clip. **2 AAA Duracell batteries included and installed. Like new in original box. Lightweight. Approximately 10.5" high.