Strong G4526 σάκκος sakkos · sackcloth

Revelation

1. Revelation 6:12
   And I beheld when he had opened the sixth seal, and, lo, there was a great earthquake; and the sun became black as sackcloth of hair, and the moon became as blood;
2. Revelation 11:3
   And I will give power unto my two witnesses, and they shall prophesy a thousand two hundred and threescore days, clothed in sackcloth.