And what can make you know what is sijjeen?
Quran - Verse : 8, Surah : Al-Mutaffifen : 83, Chapter : Those Who Deal in Fraud | 83:8

وَمَا أَدْرَاكَ مَا سِجِّينٌ
القرآن الكريم - آیة : 8، سورة الْمُطَفِّفِيْن : 83 | 83:8