Features: Transmitter is built in microphone, equipped with lavalier microphone, convenient to use. The transmitter can adjust the volume and frequency. Transmitter-convert sound into ultra high frequency electrical signal. 360 omnidirectional pickup, superior noise cancellation, clear sound quality. Receiver-receiving lossless signals with 0 delay to ensure perfect audio. Support headphone monitor, you can insert the earphone into the headphone jack to monitor your voice in real time. Both transmitter and receiver are built-in lithium battery, easy to charge. Compatible with DSLR and video cameras, laptop, PC, smartphone, tablet, etc. Small appearance, clip design for hands-free use. Suitable for conference, online class, interview, recording, live streaming, vlog, etc. Specifications: Model: L05A/L05B(optional) L05A: 1 Transmitter & 1 Receiver L05B: 2 Transmitters & 1 Receiver Transmission Frequency Band: 540MHz-690MHz Transmit Power: 10dBm Receiving Sensitivity: -40dBm Pickup Method: Omnidirectional Audio Frequency Response: 100Hz-20KHz3dB Dynamic Range: 90dB Signal-to-noise Ratio: 97dB Max. Input Sound Pressure: 97dB SPL Power Supply: Built-in Rechargeable Lithium Battery Item Size: 6.5 * 5.0 * 2.6cm / 2.6 * 2.0 * 1.0in Item Weight: 43g / 1.5oz Packing List: 2 * Transmitter 1 * Receiver 2 * Lavalier Microphone 1 * Phone Cable 1 * Camera Cable 1 * Charging Cable 1 * Type-C to 3.5mm Adapter 1 * User Manual(English)