SCK2.2 Enclosures¶ These are enclosures for the SCK2.2 and the sensors it supports. Most enclosures in this section are the same as the ones in SCK2.3. Variants¶ Smart Citizen Kit 2.2 PID TGS HCHO Grade | advanced Measure Indoor or Outdoor Air Quality with this unit. Beyond the metrics from the kit, it can measure CO2 with a very reliable CO2 sensor! SCK2.2 + Alphasense (B-Series) Grade | advanced SCK2.2 with an Alphasense B-series sensor. SCK 2.2 Grade | intermediate SCK2.2 basic enclosure. SCK2.2 + 2x Alphasense (A-series) Grade | intermediate SCK2.2 with two Alphasense sensors (A-series). SCK2.2 + CO2 Grade | intermediate SCK2.2 with CO2 sensor. SCK2.2 + CO2 and 2x Alphasense (A-series) Grade | intermediate SCK2.2 with CO2 and two Alphasense sensors (A-series). SCK2.2 + CO2 and HCHO Grade | intermediate SCK2.2 with CO2 and HCHO sensor.