The Beyerdynamic Opus 669 Wireless Handheld Microphone System is an ideal solution for vocalists and presenters. The Opus 669 features the NE 600 S diversity receiver and SDM 669 handheld microphone transmitter with DM 969 microphone capsule. The capsule's dynamic element and supercardioid polar pattern yield high SPL, low distortion and a high degree of feedback rejection. The Opus 669 features true diversity reception and 16 user selectable UHF frequencies for stable, interference-free wireless signal on stage, rehearsals and in the studio. The transmitter operates for up to 20 hours on a pair of 1.5V AA alkaline batteries and features a silent on/off switch, and gain level adjustment.