Cough, chest distress, vomiting, insomnia, rheumatic heart disease, tachycardia, arrhythmia, angina, intercostal neuralgia, etc.

On the back, next to the spinous process of the 4th thoracic vertebra at 1.5 cun lateral to the midline. (This acupoint is bilateral, one on each side.)

Sit up straight and lower your head. Count down from the spinous process of the 7th cervical vertebra to the 4th thoracic vertebra, which is the 4th thoracic vertebra's spinous process, then measure 2 horizontal fingers lateral from its lower edge, and press where there is a sensation of soreness and swelling, which is the location of this acupoint.