The Honeywell Series 3000 range of transmitters provide comprehensive monitoring of toxic and Oxygen gas hazards in potentially explosive atmospheres with its proven Electrochemical sensing technology. Suitable for mounting both indoors and out, they are available in two versions and offer excellent versatility. The MkII is contained in a flameproof housing, has an intrinsically safe sensor connection and is for use in predominantly Zone 1 applications. However with the use of the optional remote mounting kit the sensor of the MkII can be mounted in a Zone 0 environment. The MkIII is for use with a separate suitable IS barrier allowing the complete transmitter to be used in Zone 0 applications.