PGmc keluz Etym 2

Hi Rua ! I just created an Etymology 2 at Proto-Germanic *keluz (“throat”); however, the Inflection table insists on displaying the term as a u-stem despite the fact that I am explicitly setting the stem to "=z". Can you please check ? Thanks !

z-stems end in -az in the nominative singular, so -uz would not match. How do you think this would be inflected?