This ionic sports watch is made with environmental protected grade of silicone rubber, mixed with Eli Negative ion and anti bacteria powder in production.The ions products will emit negative ions and infrared ray. When wear next to the skin, it enables the body to absorb them and travel through the blood and lymphatic system to the body cells. As a result, it can make you calm, soothe, and relax your mind, ease your body tension, promote restful sleep, improve concentration, increase level of energys, strengthen your resistance to the effect of stress, boost your metabolism, enhance your immune function, and an overall improvement in well-being. -ultra light weight (10 grams only), ergonomic design, fashionable colors -10 meters water resistance -negative ion (anion) emittance -far infrared ray emittance (more than 90%) -high quality silicone rubber, mixed with Eli negative ions and anti bacteria powders in production -size: small-16 cm (medium-17cm and large-18cm are also available in my other listings) -color: red,green,pink,blue, black, and white (or as your requests)