The HS8287HH is a dual channel handheld wireless microphone system designed and engineered for professional performance and home karaoke use as well. It s a very cost-effective unit compared with some other wireless microphones you may find elsewhere. Best of all this unit is a PLL synthesize system with excellent frequency stability as provides long range transmission up to 150 feet. The wireless microphones takes 2 AA batteries. Additionally the system has both mixed TRS output and individual XLR outputs (TRS male to male cable included).SPECIFICATIONS:Carrier Frequency Range: VHF 170 - 210 MHzStability: ? 0.005%Operation Temperature:-10?C ~ +70?CMax S/N: > 100dBFrequency response: 20Hz ~ 18KHzMaximum Operating Range: 165 ft.