Feature: 1. Dual Modes and Functions: Rich interface design, dual receiving and transmitting modes, rich interfaces, easy switching. The functions include receiving + transmitting + call 3 in 1. 2. Stable Connection: With the latest Bluetooth chip and well designed software, upgrade your old equipment to Bluetooth function without replacement, but also promises to give you a CD like auditory feast. 3. Working Hours: 8h for RX mode, 5h for TX mode. Built in 200mAh Li‑ion battery (included), it can support Bluetooth adapter once fully charged to provide long time use. 4. Intelligent Charging: When in a low battery state, the adapter can be plugged into the power supply for charging while working. Work while charging, allowing you to enjoy more fun. 5. [Universal Compatibility] This Bluetooth 5.1 receiver transmitter is very suitable for home theater, stereo and car speakers, as well as smart phones, and for Android devices. Specification: Item Type: Bluetooth Transmitter Receiver Material: ABS Model: BT-22 Bluetooth Version: 5.1 Bluetooth Name: BT-22 Effective Open Distance: Approx.15m / 49ft Performance: Stereo HiFi Level Battery Capacity: 200mAh Li-ion Battery (included) Working Hours: RX 8h, TX 5h Frequency Response Range: 10Hz-20kHz Signal To Noise Ratio: ＜110dB Product Function: Receiving + Transmitting + Call 3 in 1. Package List: 1 x Bluetooth Transmitter Receiver1 x 3.5mm Cable1 x Type C Charging Cable1 x RCA Cable1 x Manual