'Linen' in the Bible

Samson said to them, "Let me tell you a riddle now. If you can declare it to me within the seven days of the feast, and find it out, then I will give you thirty linen garments and thirty changes of clothing;

but if you can't declare it to me, then you shall give me thirty linen garments and thirty changes of clothing." They said to him, "Put forth your riddle, that we may hear it."