There are two versions of the Polarization Cell Replacement for addressing hazardous (classified) locations: the standard PCR for Class I, Div 2 and Zone 2 areas, and the PCRH for Class 1, Division 1 and Zone 1 areas. Featuring the same technology as the PCR in an explosion-proof package, the PCRH has been fully tested and listed by Underwriter's Laboratory (UL) to the US and Canadian standards, as well as to European standards ATEX and IECEx.