1Set Diesel Engine Frequency Conversion Sound Group Module Powered By Receiver/2S Lipo Port for DIY RC Models.This module connects between the receiver and the ESC to produce variable-frequency diesel engine sound based on throttle input.The center position (1500 ± 50 µs) corresponds to the lowest frequency, with frequency increasing proportionally as the throttle stick is moved upward or downward.Input voltage: 3.6V–8V when powered by receiver; compatible with 2S LiPo power source.Board size: 34 mm × 14 mm.Supports connection to 8 ohm, 0.5W–6W speakers.Speaker not included.Designed for integration into DIY RC models requiring realistic sound feedback. This product is not manufactured by the brand.Model and brand mentions are for compatibility guidance only.