Beach Flour Sack Towels. Beach Time 3 Piece Flour Sack Towel - These Flour Sack towels are soft, durable, lint free, and 100% cotton! They measure about 26"x26" and come in a set of three. They are multipurpose towels and are very absorbent. Two towels are a solid sea blue color while one is white and features a flip flop design.