These are the original cold-weather socks, carefully selected for their materials and crafted with comfort and manufacturing methods optimized for cold-weather care, based on the guidance of Dr. Shindo. Seikatsuken are the only cold-weather socks supervised by Dr. Shindo. This set includes three pairs (five-finger socks): ① 100% silk (natural) - Size M ② 50% silk, 50% cotton - Size M ③ Seikatsuken - 50% silk, 50% cotton - Size M ⭐︎This does not include the book.