The pictured item is in all probability a Czech piece, but any attribution calling it Tango would be incorrect. Tango, by definition is a colored piece having two distinct glass colors as the design. Both colors need to be glass. It is not necessary for the rim to be involved in the second color, as it can be the handles, the rim, a foot, or stripes or swirls in the glass, or a combination of the above, as long as the glass composition of the piece consists of only two colors of glass. Although Loetz developed Tango glass it was manufactured by many companies and can be difficult to attribute correctly without a very distinct known form, or a recognized mark from a company such as Loetz or Kralik. There are instances of enamel decorated Loetz Tango, but in many cases the enameling was applied by other companies such as Hosch as shown in Truitt Collectible Bohemian Glass 1840-1940, where a plate from a Carl Hosch catalog shows decorated Loetz Tango pieces. Most pieces of decorated Tango I have seen or are familiar with are generally decorated in a rather simplistic fashion.
Additionally, the attribution of almost all Tango to Powolny is incorrect. It is my understanding that, although he designed some Tango pieces (a handful, most commonly exhibiting vertical stripes), he is not responsible for the decor. Alfredo Villanueva-Collado refers to the Powolny attribution as an "internet Urban Legend".
There are other "two color" decors by Loetz which, depending on the style, fall within the Ausfuhrung Decors such as Ausf 162, 216 and 166.
I would describe the above vase as an enamel decorated Czech vase, manufacturer unknown.
Craig