Set includes two wireless microphones and a BMB unit. - Brand: JOYSOUND - Model: BMB Infrared wireless microphone set 1 receiver 1 light receiver Stored item. Operation was confirmed by using two microphones alternately for two songs, and they worked without problems, but long-term operation has not been confirmed. Rechargeable batteries are included. They are used, so I don't know how long they will last, but you can charge them to use, or you can use two AA batteries. Thank you for viewing.