Which frequency version to order
Z-Wave products use a different wireless frequency globally. See 'Z-Wave frequencies' for detailed information on which frequencies have been legally approved for use in different countries.
About Smart Switch 6 (USA model) from Aeotec
Z-Wave smart plug with energy monitoring and multi-colour light ring for energy-use indication. This Type B model, most commonly used in the United States, does not feature a USB side port as some other models of Smart Switch 6 do.
Aeotec maintains Smart Switch 6 user guide and setup information at that link.