Zero Calibration Kit for all CO2-Transmitters, incl. 10 cartridge filters

<strong>Features</strong>
<ul>
 	<li>Instrument generates CO2 - free air for calibration of CO2 sensors at "zero point"</li>
 	<li>Average absorption time of 9 hours per cartridge</li>
 	<li>Power supply via AC adapter or internal rechargeable battery</li>
 	<li>Charging function</li>
</ul>
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