Signal stabilizer 15 meters barrier-free transmission, stable signal with zero delay and no stuttering, suitable for car, office, entertainment, and other household applications Supports TF card plug-and-play; insert TF card for direct playback. Built-in smart decoder supports music playback from TF card in multiple formats (MP3/WAV) Upgrades non-Bluetooth devices to Bluetooth connectivity with LED digital display High-definition LED digital display shows real-time status with non-dazzling cold light. Equipped with Bluetooth 5.3 chip for improved sound quality and enhanced performance Built-in 300 mAh lithium battery provides up to 8 hours of continuous use for listening, navigation, and calls. Four modes for versatile use: one-touch switching between receiving, transmitting, FM, and TF card modes Bluetooth transmit power: 7dBm Output impedance: 32 Frequency response: 20-20kHz Signal-to-noise ratio: 90dB Microphone sensitivity: -42dB Bluetooth receiving range: 15M FM transmitting range: 2M FM transmitting frequency: 87.5-108.0MHz TF card playback supports auto power-off memory function, compatible with up to 32GB cards Input parameters: 5V/2.1A Charging time: approximately 2 hours Listening time: approximately 6 hours Functions: Bluetooth transmit (TX), Bluetooth receive (RX), TF card playback Bluetooth version: 5.3 Compatible with computers, projectors (transmitting mode), speakers, headphones, and vehicles (receiving mode) AUX interface included Built-in 300mAh battery with protective circuit Color: As shown Material: ABS Package Contents: 1 x Bluetooth Transmitter Receiver Note: Light reflection and display differences may cause slight variation between the image and actual item. Measurement tolerance: 1-3cm