Jeremiah 52:21

And [concerning] the pillars, the height of one pillar [was]
eighteen cubits
As in ( 1 Kings 7:15 ) ; said to be thirty five, ( 2 Chronicles 3:15 ) ; of the reconciliation of which, (See Gill on 2 Chronicles 3:15): and a fillet of twelve cubits did compass it;
a thread or line of that measure encompassed each of the pillars, ( 1 Kings 7:15 ) ; and the thickness thereof [was] four fingers;
either of the pillar, or the fillet about it; that is, the brass of it was four fingers thick: [it was] hollow;
that is, the pillar was hollow.