וַיִּתְפֹּ֣שׂ אֲחִיָּ֔ה בַּשַּׂלְמָ֥ה הַחֲדָשָׁ֖ה אֲשֶׁ֣ר עָלָ֑יו וַיִּ֨קְרָעֶ֔הָ שְׁנֵ֥ים עָשָׂ֖ר קְרָעִֽים׃
And Ahijah laid hold of the new garment that was on him, and rent it in twelve pieces.
Read kabbalistic (mystical) interpretation of I Kings 11:30: and classical mystical sources.