'Leather' in the Bible

Then he took his stick in his hand, and got five smooth stones from the bed of the stream and put them in a bag such as is used by sheep-keepers; and in his hand was a leather band used for sending stones: and so he went in the direction of the Philistine.

And David put his hand in his bag and took out a stone and sent it from his leather band straight at the Philistine, and the stone went deep into his brow, and he went down to the earth, falling on his face.

So David overcame the Philistine with his leather band and a stone, wounding the Philistine and causing his death: but David had no sword in his hand.