Xtreme Research Skyscan Detector 120V A/C Adapter (Detector Not Included) Detects lightning as far as 40 miles away and accurately ranges its approach by both an audible tone and by four LED's which are ranged in miles (0-3, 3-8, 8-20, 20-40) Requires (2) 9V batteries (not included) AC Adapter not included Rugged weather resistant case