This is an abstraction that packs numbers with all its inlets being hot (similar to Max's [pak]).
Since its inlets are being created dynamically, you can't save any connections to this abstraction, but it can be really useful for testing things...
Get it here.

@alexandros just fyi pd-extended's initbang allows inlets to be created before the object is created, allowing connections to remain

@seb-harmonik.ar mentioning that you brought it back to my memory, but I'm using vanilla and don't have [initbang]... thanks anyway..

Made an extended version. called [extendedPak], which uses [initbang], so you can save its connections. I've changed the name of the repository, so its URL has changed too. Get it here (I changed the URL in the original post too, just to be sure...).

Fixed the connections issue with a hack provided by IOhannes m zmölnig from the Pd list. Now saving connections to the vanilla abstraction is possible. Check it as text (last line) to see how this is achieved.
Also made [vanillaJoin] and [extendedJoin] which work like Max's [join], which packs a list (with all hot inlets) without needing to specify whether you provide a float or a symbol (could possibly add pointers to a future version...).
Enjoy..