2 PACK Plane Finder Tracer Tracker Lost RC Aircraft Helicopter Drone - Apex RC Products #3000 Includes 2 finders - makes finding a lost downed r/c model easy! Loud 85 decible alarm - to activate simply turn off your transmitter after 10 seconds the alarm will begin to beep. Super easy to install - plugs directly into the receiver or inline with a servo. Input voltage 4. 8v - 6. 0v. Weight 4. 5g.