The easy PLUG'N'GROWTM calibration method will give a perfectly calibrated CO2 sensor every time in 30 minutes or less! This kit can be used to calibrate CO2 controllers and external sensors of any make and any model. A CO2 sensor is not accurate at the beginning and at the end of its measuring range, namely about "0" and around 5000 PPM (parts per million). Most indoor gardeners wish to enrich garden concentration from 800 to about 1500 PPM. Nova Biomatique, Inc. developed its unique calibration method at 1000 PPM for the most accurate calibration. With careful handling, the easy PLUG'N'GROWTM calibration method will give a perfectly calibrated controller. The gardener will get accurate readings and as good a CO2 control as the equipment allows. This kit contains all the required parts in a useful toolbox: • Calibration gas bottle at 1000 PPM CO2 (20 calibrations)* • Gas flow regulator • Rechargeable air pump with charger • Flexible clear tubing • 2 Pinch clamps to cut air flow in the clear tube • 20 Clear calibration bags* • 4 Reusable Tie Wraps 25 Labels to affix to calibrated controllers