Amazon Shure  
Shure SM81-LC Cardioid Condenser Instrument Microphone for Guitar, Piano, and Cymbals, Includes Swivel Adapter, Attenuator-Switch Lock, Windscreen, Carrying Case, No Cable Included (SM81-LC)
This microphone requires phantom power and performs best with a 48 Vdc supply (IEC-61938). However, it will operate with slightly decreased headroom and sensitivity with supplies as low as 11 Vdc. Most modern mixers provide phantom power. You must use a balanced microphone cable: XLR-to-XLR or XLR-to-TRS.
The SM81 is ruggedly constructed. It operates on phantom power and performs over a wide range of temperatures and humidity conditions. It is furnished with a swivel adapter, attenuator-switch lock, foam windscreen, and case for carrying and storage. Other accessories are available.
20 Hz to 20 kHz frequency response. Flat response curve for accurate reproduction of sound sources.
Low noise and high output clipping level. Low distortion over a wide range of load impedances.
Cardioid polar pattern, uniform with frequency and symmetric about axis, providing maximum rejection and minimum coloration of off-axis sounds
Low RF susceptibility
Selectable low-frequency response: flat, 6 or 18 dB/octave rolloff
0 dB/10 dB lockable attenuator switch
Rugged steel construction for durability. Field-usable over wide range of temperature and humidity conditions.
Cardioid condenser instrument microphone offers a wide frequency response and low self-noise. Features include flat response curve, low noise and high output clipping level, low distortion over a range of load impedances, and low RF susceptibility.
Shure SM81-LC Cardioid Condenser Instrument Microphone for Guitar, Piano, and Cy
Amazon IQAir  
IQAir PreMax Prefilter - Genuine Replacement Air Filter For IQAir HealthPro Series - Controls Coarse and Fine Particles - Dust, Mold Spores, and Powder - Swiss Made Filters For Air Purifiers
PREFILTER REPLACEMENT FILTER: Genuine PreMax replacement from IQAir! Designed for our HealthPro Series Air Purifiers, the PreMax air purifier pre-filter traps coarse, fine, and micro-particles, including dust, mold spores, and powder.
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IQAir PreMax Prefilter - Genuine Replacement Air Filter For IQAir HealthPro Seri
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