Dual UHF Wireless Microphone with Bluetooth Receiver, No Need To Set, Just Plug and Use. Perfect for Karaoke, Speech, Meeting, Performance, Indoor or Outdoor. K380A not support For multiple sets using, but our K380S Rechargeable Wireless Microphone can support 10 sets at max for Simultaneously Using.1/4 Inch(6.35mm) Receiver Input designed for Outdoor Karaoke Speaker, PA Speaker System, Power Amplifier, etc. K380A not for Bluetooth Speaker, Phone, PC. The Receiver can not search and connect with other Bluetooth Devices. We only can use phone to search and connect the Receiver to play background music, Receiver can transfer both voice and music signal to speaker.Microphone and Receiver use UHF Connection Technology, Indoor range >50ft(Outdoor range >100ft); Receiver with Bluetooth to play background music(BT Range 16ft - 33ft Outdoor); Frequency Response 50Hz - 18kHz, SNR >70dB; 10 UHF variable channels(CH01-CH10); 2 x Microphone Windscreen as a Bonus Microphone use 2 x AA batteries(Included); Bluetooth Receiver(Built-in rechargeable battery).Advanced connection and after sales: If your microphone has no sound, make sure you have enough power for the microphone and receiver. Insert the MIC jack, Not an AUX jack. If you find no sound from the mic, you need to re-pair..1-Year Warranty And Precautions: KITHOUSE offers1 year warranty and free replacement service.Can write to us when you have any questions.Your problems and suggestions is the key for us to improve.