Definitely not cotton. I bought a white kit for my daughter to dye her tie. The paint didn't stick to the sock and washed out immediately after rinsing. This is an image of toddler socks and 74% cotton socks dyed the same colors in the same batch. Don't buy them to dye a tie or if you need cotton. According to the packaging, they are made of 60% cotton, but they are not.
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