Features: Bluetooth-compatible version 5.4 chip, rejecting latencies and lags. Insert and use, no drive required. Two styles to choose from: 1 receiver 1 transmitter, 1 transmitter 2 receivers. Suitable for devices without bluetooth-compatible function such as computer, mobile phones, music player, etc. Please note that this transmitter cannot be connection to headphones and speaker. Note that the receiver cannot be used with the bluetooth-compatible connection of phones tablets, and can only be used with the accompanying transmitter. Specifications: Component: ABS Color: Black Type: 1 receiver 1 transmitter, 1 transmitter 2 receivers(optional) Size: about 72x32x14mm/2.8x1.2x0.5", 58x29x17mm/2.2x1.1x0.6" Model: LC3 Bluetooth-compatible Version: BLE5.4 Frequency: 2.402GHz-2.480GHz Ttransmission distance: 10m Transmitter parameters: Build in battery: 250mAh Aux input: 3.5mm interfaces, USB C Receiver parameters: Build in battery: 150mAh, 3.5mm aux output interfaces Package Includes: 1x Bluetooth-compatible Transmitter with 1x Receiver/with 2x Receivers (optional) note: Please allow 1-2cm errors due to manual measurement. Please allow for slight color differences due to different display resolution.