the cotton has very little powder ash and no particles or lumps in the hand.and the burning ashes of chemical fiber socks can be condensed into particles or clumps, which are hard to be crushed by hand.the cotton socks of pure cotton are high carbon plant fiber, and the smell of paper after burning is very different from that of chemical fiber burning.
in addition, cotton socks wear a long time, the surface layer will fall off layer by layer, remember is a layer, the better cotton, the better sports socks show more obvious.
don't look at the old socks. it's a good pair of socks.
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