Features 1. Wireless Karaoke Microphone System: UHF wireless microphone produces high-quality clear sound without distortion. The professional dynamic microphone set comes with 3 built-in rechargeable and replaceable batteries. 2. 1200mAh battery for extra long usage time: 3 rechargeable replaceable 18650 batteries, no need to buy batteries, 10 hours of work with a full charge within 3 hours. The microphone display shows the battery level and signal strength in real-time. The microphone and receiver are professionally drop-tested for high impact resistance, lighter weight, and higher abrasion resistance. 3. Signal stability: The high-sensitivity professional dynamic microphone extends the working range to 160ft (50m), which solves the problem of tangled wires. UHF wireless microphone with built-in cardioid pickup pattern provides a clearer signal and better sound quality, reducing the chance of interference and dropped calls. 4. Plug and Play: Just plug the receiver into the MIC jack, and the receiver will automatically sync its frequency with the microphone, batteries, adapter plugs or cables, and other accessories that are included in the package and ready to use when you receive it. 5. Compatible with a wide variety of devices: The microphone is designed to work with devices that have a 6.35mm (1 or 4") or 3.5mm (1 or 8") MIC input. Suitable for karaoke machines, mixers, jukeboxes, audio amplifiers, PA systems, powered speakers, voice amplifiers, truck speaker systems Specification: Name: wireless microphone Microphone: moving coil microphone core Input voltage: 5V Microphone 18650 lithium battery: 600MAH Receiver 18650 lithium battery: 600MAH Endurance: 3 hours Signal-to-noise ratio: 64DBM Transmission Delay: 5MS Sensitivity: -42DB Frequency range: 20-20KHZ Transmission distance: 15- 25 meters without obstacles Type-c charging jack, audio input DC6.35mm DC3.5mm computers, tablets, speakers, amplifiers, cameras and other devices How to Use: 1. Put rechargeable batteries in the receiver and microphones. 2. Plug the receiver into the MIC input of your audio device. 3. Turn on the microphones and the receiver. Warm Tips Before Use: Charge the microphones and receiver over 3 hours before you begin your first use because their batteries were not fully charged when they were packed. Make sure the microphones and receiver have enough power before using them. If fail to connect, please Turn off the microphones and receiver, then turn them on again Package Includes: 1 or 2x UHF Wireless Microphone 1 or 2x Anti-Slip Ringsrandom colour 1 or 2x blowout preventer 2 or 3x 18560 battery 1x 6.35mm to 3.5mm Adapter 1x Receiver