Czech "Tango" covered jar with applied flower

Jars like this seem to be far less common than the vases with similar décors. This jar is 4½" (11.3 cm) tall with the lid in place and equally wide. It has a yellow and clear stuck-on flower with cobalt blue trailing leaves on a clear cased red ground.

The clear casing arouses my curiosity. There is a series of "Tango" shapes, all with the same striated clear casing (notice the lid) that makes me think they were all made in the same place. I have heard suggestions of which company made these pieces. I have my suspicions, but would certainly like to hear some current opinions.