What does an ``EX `` suffix mean on a XB4 push button catalog number?

Issue:
Trying to identify form EX on XB4, 22mm buttons.

Product Line:
Push Buttons and Operator Interface

Environment:
22mm Operators

Resolution:
Form EX indicates a product that meets ATEX requirements (for an explosive dust atmosphere per IEC Directives 99/92/EC and 94/9/EC).  These products have not been commercialized or sold in the USA.

Released for:Schneider Electric Singapore