Wireless Microphone Headset System: Built-In High Sensitivity Condenser Microphone, Transmission Distance Upgrade To 160 Feet (50m) Signal Stability, No Delay, No Radiation, Anti-Howling, Anti-Jamming , Constant Frequency , Clearer Sound Quality. Charge And Work Of Wireless Microphones: The Transmitter And Receiver Are Built-In 120 Mah Rechargeable Lithium-Ion Batteries That Can Offer About 6-8 Hours Working Time. Usb Cable Has Two Micro Usb V2.0 For Charge For The Transmitter And Receiver At The Same Time, Fully Charge Is Only 2.5 Hours. Perfect Application: The Plug On The Receiver Is 3.5mm. For 6.35mm jacks,Please Use The Additional 6.35mm Adapter(Included)To Connect More Equipments. Humanized and thoughtful design: the microphone will automatically shut down if you do not use the microphone within 45 minutes of no operation, saving power and worry. Built-In Cardioid Polar Pattern Condenser Microphone,Widely Applied To Conference,Speech, Web Podcast, Outdoor Live, Yoga Instructor,