Vexit

A vexit is a Sis moderated transvex portal, which is usually, but not exclusively, part of the SlabWide tube system.

As with all transvex membranes, their status can range from locked hard through permission only, destination acceptance required, soft purpose or free transit. Their visual appearance ranges from camouflaged through opaque, translucent, invisible and radiant but, because these states are not always linked to their transit status, Sis query is advisable before personal transition.

Seeing as tube transvexes are almost always two-way, the most frequently asked question is 'why aren't they also called ventrances?' - to which the correct answer is 'are you a cake?'.