Free frequency modulation, adopts uhf 676mhz to 607 mhz frequency band, strong anti-interference, applied to karaoke, party, business meetings, speech or other outdoor and indoor activities.<Br/>features:<br />wireless handheld microphone system for karaoke, party, business meetings, speech or other outdoor and indoor activities.<Br />adopts uhf 676mhz to 697mhz frequency band (channel a: 677mhz-686mhz; channel b: 687mhz-696mhz), strong anti-interference.<Br />with automatic mute and shock elimination circuit avoiding the impact and noise of the switching, extremely high pick-up sensitivity and fine tone quality make your speech or singing more clear.<Br />the wireless transmission distance is about 30 to 50 meters, multiple devices can be used simultaneously without interference or frequency hopping.<Br/>specifications:<br />microphone quatity: 1pcs, 2pcs (optional)<br />frequency response: 676-697mhz<br />oscillator: dsp chip frequency lock<br />frequency stability: ±10ppm<br />distortion: ≤0.5%<Br />sensitivity: -95 to 71dbm<br />sound frequency: 40-18000hz<br />snr: ≥ 90db<br />rf power: 10dbm<br />audio output: 1/4&#34; unbalanced output 300mv<br />receiver battery: 3.7V, 150mah<br />microphone battery: 2 * aa battery (not included)<br />receiver size: 125 * 35 * 20mm / 4.9 * 1.4 * 0.8In<br />receiver weight: 49g / 1.7Ounce<br />microphone size: 230 * 40mm / 9.1 * 1.6In<br />transmitter weight: 203g / 7.2Ounce<br />package size: 285 * 140 * 100mm / 11.2 * 5.5 * 3.9In<br />package weight:<br />1pcs microphone: 470g / 1.0Lb<br />2pcs microphone: 670g / 1.5Lb<br/>package list:<br />1pcs microphone:<br />1 * microphone<br />1 * receiver<br />1 * antenna<br />1* usb cable<br />1 * 3.5Mm converter<br/>2pcs microphone:<br />2 * microphone<br />1 * receiver<br />1 * antenna<br />1* usb cable<br />1 * 3.5Mm converter