Since my 10 year old son hates the seams in his socks, I ordered the Jefferies seamless socks to try. When he tried them for the first time, he really complained. Since then, however, he has not complained about it. If you are wondering, there is a seam on the inside as you can see in my photo. There is no seam where the white part meets the gray, but you can feel the bump if you run your fingers there since the gray part is slightly higher. There is a seam in the gray area of the toe, but it is very smooth. So I wouldn't call them "seamless" but they are probably the most comfortable socks you can find.
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