Surah Al-Haqqah, Verse 32

ثُمَّ فِي سِلۡسِلَةٖ ذَرۡعُهَا سَبۡعُونَ ذِرَاعٗا فَٱسۡلُكُوهُ٣٢

thumma fī sil'silatin dharʿuhā sabʿūna dhirāʿan fa-us'lukūhu

Then into a chain whose length is seventy cubits insert him."