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  • Replacement CO sensor (A-505)
  • Replacement NO2 sensor (A-506)

This product is an accessory for the following products:

Dwyer GSTA & GSTC CO / NO2 Gas Transmitters
Carbon monoxide & nitrogen dioxide transmitters with field selectable analog or digital outputs & long life electrochemical sensor

The Dwyer GSTA & GSTC replacement gas sensors have a 4-year typical life span. The CO (A-505) and NO2 (A-506) sensors are each sold separately and are field replaceable.