【Digital Display】Features a digital tube display for clear and easy-to-read information at a glance. 【Fast Charging Support】Equipped with QC3.0 fast charging output, compatible with Quick Charge 3.0/2.0, for Huawei FCP, for Samsung AFC, USB BC1.2 DCP, and for Apple 2.4A charging protocols. 【High-Quality Audio】Supports stereo FM transmission and playback of various audio formats including WMA, MP3, WAV, APE, and FLAC for superior sound quality. 【Advanced Bluetooth-compatible Functionality】Bluetooth-compatible 5.0 with A2DP, AVRCP, HFP, and HSP profiles, enabling hands-free calling and stereo music streaming with DSP technology. 【Enhanced Call Quality】Incorporates CVC technology for echo cancellation and noise suppression during calls. 【Battery Voltage Detection】Monitors your car's battery voltage, providing an added layer of vehicle care. Specifications: Model: BC77 Net Weight: 46g Product Dimensions: 3.85*3.9*9.5cm Operating Voltage: 12V~24V (10-26V limit) Operating Temperature: 0-50℃ Supported Audio Formats: MP3/WMA/WAV/FLAC Signal-to-Noise Ratio: >60dB USB Ports: USB1 (U-disk/5V/1A), USB2 (QC3.0 3.6V-12V) Bluetooth-compatible Version: 5.0 Bluetooth-compatible Range: Up to 10M Microphone Range: 0.5-2M FM Transmission Frequency: 87.5MHz-108.0MHz FM Mode: Stereo digital PLL frequency locking