Quoting Commentary for I Kings 7:21

וַיָּ֙קֶם֙ אֶת־הָֽעַמֻּדִ֔ים לְאֻלָ֖ם הַֽהֵיכָ֑ל וַיָּ֜קֶם אֶת־הָעַמּ֣וּד הַיְמָנִ֗י וַיִּקְרָ֤א אֶת־שְׁמוֹ֙ יָכִ֔ין וַיָּ֙קֶם֙ אֶת־הָעַמּ֣וּד הַשְּׂמָאלִ֔י וַיִּקְרָ֥א אֶת־שְׁמ֖וֹ בֹּֽעַז׃

And he set up the pillars at the porch of the temple; and he set up the right pillar, and called the name thereof Jachin; and he set up the left pillar, and called the name thereof Boaz.

Rashi

thirty-five cubits long i.e., the height. And in I Kings (7:15): “And he cast the two pillars of copper, eighteen cubits, etc.” Rabbi Solomon (Rashi to Kings) explained that he cast them both together and subsequently divided them in two, and the missing cubit is not counted because it is unlike the work of the rest of the pillar, as is written there in the section (7:22): “And upon the top of the pillars was lily work.” Rabbi Joseph [Kara] also explained it in this manner, but it is not acceptable to me, for what is the meaning of its height being eighteen, but this is how I heard it, that he surely cast them both together, and then divided them in two; so we find that each one was seventeen and a half cubits, and the capital, which was the chapiter, as is stated there, its thickness was half a cubit, making each one eighteen cubits.
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Rashi

The two columns. Which he placed at the entrance hall,21He placed them at the entrance to the Temple’s hall. See v. 21 below. Yachin and Bo’az.
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Rashi

and pillars to the posts instead of Jachin and Boaz (I Kings 7:21) which were in the First Temple.
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