Feature Highlights: 1. Versatile Connectivity – Equipped with a 5mm interface and Bluetooth 4.1, this adapter supports 2-in-1 functionality, allowing seamless connection to headphones, mobile phones, speakers, and car audio systems. 2. Intelligent Operation – Features call number display, voice prompts (Chinese‑English bilingual, default English), pairing timeout shutdown (after 5 minutes), and low‑power reminders (alerts below 2V, auto‑off at 1V). 3. Convenient Control – Power on/off with a 5‑second button hold. Adjust volume with +/- buttons, control music playback (play/pause, skip tracks), and manage calls (answer/end, reject with hold, cancel redial). 4. Clear LED Indicators – Alternating red/blue lights during pairing, slow blue flash when connected, and red flash for low battery. 5. Efficient Power Management – Built‑in 180mAh rechargeable lithium battery provides up to 250 hours standby, ~10 hours call time, and stable current across all modes (music, call, standby, charging). Product Details: This Bluetooth audio receiver enables wireless streaming to AUX‑compatible devices such as car stereos, speakers, or headphones. It ensures stable transmission within a 15m range, supports HFP/HSP/A2DP/AVRCP protocols, and features intelligent noise reduction for clear calls. The compact, lightweight ABS housing offers plug‑and‑play setup with no tools required. Specifications: - Interface: 5mm AUX - Bluetooth Version: 4.1 - Battery: 180mAh rechargeable lithium polymer - Standby Time: ~250 hours - Call Duration: ~10 hours - Wireless Range: 15m (49.2ft) - Frequency: 2.4Hz - Supported Protocols: HFP/HSP/A2DP/AVRCP - Weight: 25g (0.9oz) - Color: Black Package Includes: 1x Bluetooth Adapter, 1x 3.5mm Audio Cable, 1x USB Cable, 1x Instruction Manual