Palpitations, heart pain, chest and rib pain, unconsciousness, fever, madness, spasms and arm pain, etc.

On the radial side of the distal phalanx of the little finger, 0.1 cun from the corner of the nail. (This acupoint is bilateral, one on each side.)

Extend the fingers with the palm facing down. Along the base of the little fingernail and the radial edge of the little finger (the junction of the palm and back, also known as the red and white skin boundary), the intersection point is the location of this acupoint.