The left container was sold by the WW with the article number K 0359, the right container lacks an article number.
In 1912 the Hora-Grill family commissioned Eduard Wimmer-Wisgrill and the Wiener Werkstätte with providing the furniture and fittings for their apartment. As part of that, these two ceramic containers were acquired from the WW in Vienna. And in fact, one of them bears the WW article number. Unfortunately this article number cannot be verified by the MAK archives.