1. Pregnant women, children, the man, patients. 2. People who use mobile phones,computers,electronic devices often. 3. People who often use Tablet PC, ,Computer,Air conditioner,Refrigerator, Oven, Printer,Washing machine, and office automation equipment. 4. People living or working in the of high-voltage, substation, radio, radar station, and electromagnetic transmission tower. Colour: Black Material: Volcanic rocks and high quality Pendant size: . 4.3 x 4.3cm Improves circulation Enhances cellular permeability, nutrition and detoxification , endurance & strength Alleviate soreness, aches & pains, and flexibility Enhances the immune and endocrine Increases energy Helps to retard the ageing process Calm the mind & focus Strengthen the body's -energy field to protect from harmful electromagnetic waves Package Contents:1 x Energy Pendant Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.