'Twelve' in the Bible

The two pillars, the one sea, and the twelve bronze oxen that [were] under the kettle stands which King Solomon had made for the {temple} of Yahweh--there was not a weight for the bronze of all these vessels!

Now the pillars, [the] height of one pillar [was] eighteen cubits, and a thread of twelve cubits surrounded it, and its thickness [was] four fingers, hollowed out.