... We have sold over 20,000sets.ApplicationFeature:- Waistband Microphone with Radio frequency, perfect for entertainment, outdoor activities.- With low consumption and ... 1 pcWarranty Card 1 pcCertification 1 pcAttention: When the machine is without enough power, pls. charge the battery in ... life span. Non-specialist, pls. don’t open the machine to repair. Any problem, pls. contact the local distributor ...