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Sea to Summit says:
The Tek Towel™ Wash Kit is a great package for staying fresh while travelling. The kit includes a towel for all over drying and a washcloth when you just need a freshen up. Each kit comes with a 40ml Wilderness Wash soap concentrate which is suitable as a bodywash, shampoo, dish and clothes detergent. Both towels are made from super absorbent and quick drying Tek Towel.