Output power: 1W8 ohms 5V/ 0.6W8 ohms 3V Signal input: Positive pulse 0.8ms to 2.0ms Sound quality: Sampling frequency of 22.05 kHz Memory: 4M, 22.05 kHz audio about 20 seconds Note: The power supply voltage of the sound group is up to 5V, and it must not exceed 5V, which is more than to burn the built-in power amplifier and single-chip microcomputer, if it is the BEC of electric regulation It is 6V, it is recommended to connect two 2A rectifier diodes in series to depower from the receiver, and the voltage drop is 1.2-1.4V to supply power to the sound group. Control mode When the control is opened, the engine sound automatically start when the throttle channel is moved for the first time, and the engine sound automatically turn off if the engine for more than 20 seconds. The engine sounds when the throttle rocker moves before it starts. Colour:As Shown Material:plastic Specification:SC0001 version Package Contents: 1X 5V Mini RC Engine Sound USB Unit Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.