What a fabulous site, Pamela...an amazing reference in so many ways.
Anne, to me it sounds like you're right - there's a taller pot available. "Hell" is one of those confusing context-dependent words. You can have "hell blau" for pale blue or "hell" alone for colorless, nevermind all its other meanings. I noticed that Brockwitz calls their glass literally "crystal white."
The cover of the earliest Walther catalog is itself a work of art!