Of coarse, dark goat's hair. Used for sacks, also for close fitting raiment in mourning; secured by a girdle (Genesis 42:25; 1 Kings 21:27; 2 Samuel 3:31).
Bibliography Information Fausset, Andrew Robert M.A., D.D., "Definition for 'Sackcloth' Fausset's Bible Dictionary". bible-history.com - Fausset's; 1878.