Wireless Karaoke Microphone PENTATONIC GTM-100A Black Uses 2 AA batteries Includes instruction manual. This karaoke microphone can be used with karaoke parlor receivers. You can enjoy it with DAM or JOYSOUND. No troublesome equipment installation or cords are needed. - Transmission frequency: Channel A 2.06MHz, Channel B 2.56MHz (switchable). - Can use the included alkaline batteries or rechargeable nickel-metal hydride batteries. Although a microphone cover was used, this is a used item, so please purchase only if you understand this.