Different batches have different wool content. The percentage varies. Also the kind of wool varies -- sometimes merino wool, sometimes non-merino wool. If you come across these in person, check the ingredients label like you're reading a box of cereal, and pick the ones with the highest percentage of merino wool, ideally. Or the highest percentage of wool, if Merino is not mentioned. Color also varies quite a bit between batches. Timberland dumps previous years socks to discount stores, so look for good prices.