The LifeStrength band contains a combination of seven minerals and gemstones which work together to combat the negative effects of overcharged bodies, such as the constant barrage of electronic devices. The LifeStength band help restore natural balance within the body by emitting anions (negative ions). Sizes: Small, medium, and large. The LifeStength bands come in five, stylish colors: Black, gray, red, blue, and pink.