The AKG WMS PRO Presenter Set is a UHF wireless sytem consisting of the AKG PT40 PRO belt-pack transmitter, AKG CK55 L lavalier microphone, and the AKG SR40 Single receiver. Easy to hide in the user's clothes, the WMS 40 PRO presenter sets provide optimum intelligibility for actors, presenters, or moderators. Ease of use and AKG reliability lets you focus on what you have to say. The transmitter operates for 30 hours off a single AA size battery. UHF operates in a higher frequency range than VHF systems. The VHF range is very highly populated with traffic, and because the VHF signal has a longer wave length, VHF radio signals pass through non-metallic walls easier than a UHF signal, making VHF wireless systems more prone to radio interference. Though more expensive than VHF wirelss, UHF is well worth the extra cost. AKG CK55 L LAVALIER MICROPHONE The AKG CK55 L is a low-profile, cost efficient clip-on lavalier microphone for applications including houses of worship, lecturers, etc. Connects to AKG PT40 PRO bodypack transmitters. The CK 55 L provides a natural sound, with a slight rise above 10 kHz for added clarity. Its cardioid polar pattern and bass rolloff combine to suppress unwanted ambient noise. AKG WMS40 SR40 UHF RECEIVER Single fixed frequency. All-metal case. High Definition Audio Performance technology ensures the legendary, realistic AKG sound and perfect audio transmission. The AKG SR40 UHF receiver is as easy as plug & play, with a fixed preset frequency to let you set up and operate quickly and efficiently. An adjustable squelch and output level control permit optimum signal matching to subsequent equipment. Professional outputs include a XLR and 1/4" jack. Rugged half-rack case for standalone or rackmounted operation. Signal/noise ratio: 108 dB (A) typ. Power supply: 120/230 V AC, 50/60 Hz, 95 ±15 mA. Audio outputs: balanced XLR and unbalanced TS 1/4" jack, adjustable from mic to line level, 2 V rms max.