Sensor Module for AL3100 or AL3500SC Breathalyzers
Sensor module for the AL3100 or AL3500SC (semiconductor) models ONLY.
You must choose between the older version of this sensor module, which is rectangular without thumbscrew, or the newer version of this module, which is square and with thumbscrew.
These sensor modules must be replaced approx. every 400 tests or at least once per year, whichever comes first.