Z-Wave technology has continued to evolve over the years with new features, firmware and chipset improvements. Over the years Leviton has introduced different product families that used different Z-Wave series chip sets. The chipset 'series' can easily be identified by the part number family of products.
300 Series - Vizia RF+ (VR***) and (DZ***) products
500 Series - Decora Smart Z-Wave (DZ***) products
700 Series - Decora Smart Z-Wave (ZW***) products