Tung's Acupuncture: 77.20 Si Zhi Name:77.20 Si Zhi 四肢穴Four LimbsLocation:3 cun below 77.19.Indication:1. Pain in extremities. 2. Neck pain. 3. Diabetes.Needling:0.6-1.2 cunTungs Anatomy:Reaction area of heart, kidney and limbs.