Features1Improve Sleep: The negative ion wrist strap can balance positive and negative charges, enhance body functions, improve sub health, and improve sleep quality. 2Anti Static: Suitable for running, cycling, jogging and other sports. Especially suitable for autumn and winter anti static, to solve the trouble of electrostatic shock. 3Adjustable: Anti static wrist strap with adjustable length of 17?23cm, suitable for most people wrist circumference, universal for men and women. 4Silicone Material: The negative ion sports wrist strap is made of soft and comfortable silicone material, durable, waterproof and nice wearing experience. 5Portable: Anti static bracelet with a compact size, is light weight, portable and stylish. A great birthday gift, Christmas gift, Anniversary gift.SpecificationItem Type: Anti Static WristbandSize: Approx.16 x 247mm / 0.6 x 9.7inAdjustable Size:17-23cm / 6.7-9.1inPackage List1 xAnti Static Wristband