וּבַרְזֶ֣ל ׀ לָ֠רֹב לַֽמִּסְמְרִ֞ים לְדַלְת֧וֹת הַשְּׁעָרִ֛ים וְלַֽמְחַבְּר֖וֹת הֵכִ֣ין דָּוִ֑יד וּנְחֹ֥שֶׁת לָרֹ֖ב אֵ֥ין מִשְׁקָֽל׃
Rashi on I Chronicles
for the nails, for the doors of the gates in German, negel, nails.
Rashi on I Chronicles
And David prepared... for the couplings the iron [implements] with which they join and reinforce the doors and the gates.