1、[Powerful Functions] Built in antenna, more stable signal transmission, clearer sound, no noise. Aluminum alloy appearance, more beautiful. Upgraded to infrared remote control, more convenient. Volume can be adjusted, and it also supports high and low effect adjustment. Easy installation and simple operation. Small size and light weight. 2、[Dual Device Connection and Auto Connection] Connect 2 Devices: Supports connection of 5mm port and 2 RCA port. Auto Connection: When you turn on the phone, this Bluetooth receiver will auto connect to the last paired Bluetooth device. Support music switching. Update support for U disk playback. 3、[Super Stable Connection] Bluetooth 1 chip for continuous pairing, fast transfer and 15m / 49ft (open space). With 5mm AUX port and 2 RCA ports, it can connect non Bluetooth car system, wired headphones, speakers, power amplifier, home theater, etc. Note: It is only a Bluetooth receiver, not a transmitter. So you can't use it as your keyboard, mouse. 4、[DAC Converter] Convert digital or coaxial signals to 2 RCA analog L/R and 5mm AUX. Connect to external devices such as amplifiers via standard RCA/5mm AUX. Supports sampling rates 32, 41, 48 and 96kHz. Left and right channel 24‑bit SPDIF input bitstream. Provides noise free electromagnetic transmission. 5、[Auto On and Bluetooth Reception Function] Auto on is great for use in a car or other situations where you want it to be automatic when it's plugged in. This digital to analog converter is designed for home or professional switching. Updated with Bluetooth reception function, so you can use your phone to pair with other devices via Bluetooth. 1 x Coaxial Cable1 x Optical Fiber Cable1 x 3.5 Cable1 x USB Power Cable1 x Manual1 x Remote Control1 x Digital to Analog Converter1 x 3.5 RCA Cable Item Type: Bluetooth Digital to Analog ConverterMaterial: Aluminium Alloy ShellBluetooth Protocol Support: A2DP and AVRCPTransmission Distance: Approx. 15m / 49ft (open space)Input: AUX Optical Coaxial USB BluetoothOutput: AUX RCACompatibility: For Android system, for iOS system mobile phone, tablet, TV, game console and other Bluetooth device settings, and equipment with input interfaceRemote Control Battery: 1 x CR2025, 150mAh, Built in Lithium Manganese Battery (included)