Hai Quan (M-HN-37) is located at which part of the tongue?

• A. Behind the ear, midway between Fengchi GB-20 and Yìfēng SJ-17.
• B. In the centre of the frenulum of the tongue between Jīnjīn and Yùyè.
• C. At the back of the neck, 2 cun above DU-14 and 1 cun lateral to the midline.
• D. On the lower abdomen, 3 cun lateral to the midline, level with Ren-3.

Answer: (B)

Hai Quan is a tongue point located on the underside of the tongue, right at the center of the frenulum. It sits along the midline between Jinjin and Yuye, which are two points placed on either side of the frenulum near the tongue’s tip. This central, midfrenulum position distinguishes it from points described in the other regions (behind the ear, back of the neck, or the lower abdomen), making the center-of-frenulum location between Jinjin and Yuye the correct description.