This shape exhibits a color trimmed rim in almost every example, and also has no pontil mark. This combination indicates that Welz used "Snap Tools", also known as "gadgets". The use of these devices where possible, eliminated the necessity of attaching a partially finished vase to a punty rod to finish the rim of the piece in the furnace. By eliminating the necessity for punty use, they were then also successful in eliminating much of the cold work that was done to polish pontil marks. Cold work is simply steps taken in production which do not involved the use of the furnaces. This would simplify the number of steps required for production, and in turn decrease operating costs.
I am of the belief that it was this important reduction in production costs, which contributed greatly to Welz's ability to provide exportable goods to companies such as Butler Brothers, while competing against much larger firms like Kralik.
The 1st image is from Welz production literature dated Dec 18, 1928, which I uncovered in late 2014.