Kunlun point is behind the lateral ankle, and the depression between the tip of the lateral ankle and the achilles tendon is the bladder meridian point of Foot Taiyang; According to the sea on the inside of the foot, the depression below the tip of the medial malleolus is the point of the kidney meridian of foot Shaoyin. The penetration of the Kunlun point into the sea is that the needle penetrates through the Kunlun point, inclines inward and downwards, bypasses the calcaneus and penetrates into Zhao Hai point.