Description:100% brand new and high qualityThis Alarm Buzzer is used for airplane, helicopter, multicopter, it helps you to find your drones when it out of controll and loss anywhere you can't find it easily by eyesSpecial Sound, it easily distinguishable from noise all aroundFit for: AM / FM, FM / PCM PPM systemPower supply: BEC receiverSpecification:Connect the alarm between the servo and the receiver, i.e. act as a servo extension cord.Turn on your TX. and you will hear 2 x beep sound.Do not move any of the control stick on the TX or simply turn off the the TX. You will hear a continuous beep sound after 1 minute. It will stop once u turn on your TX or move the control stick.If you ignore the continuous beep sound for around 2minutes,the beep sound will change the a louder V sound.You need to disconnect the alarm from the receiver in order to switch of the alarm.MAKE SURE THE CORRECT POLARITY BEFORE TURN ON THE TXSize Chart:Size: Approx. 13 x 17 x 12mm/0.51 x 0.67 x 0.47inchPackage Includes:1 Piece Aircraft Finder Tracker Alarm(4 Pack)