Designed to complement an active lifestyle, Bioflow Sport is awinning combination of patented magnet technology teamed with a durable, waterproof silicone wristband. Each wristband contains a powerful Central Reverse Polarity magnet encased in a smooth and comfortable one-piece strap that stretchesover your hand. Available in threesizes: Smallfits up to17.5cmwrist circumference Mediumfits up to19cmwrist circumference Large fits up to20.5cmwrist circumference Please measure your wrist carefully and order a size that fits comfortably and is not restrictive. Bioflow products should not be worn by anyone fitted with a heart pacemaker or other implant that could be affected by a strong magnetic field. PLEASE NOTE: Bioflow Sport wristbands are made of silicone. Silicone allergy is rare but those who experience it may have symptoms such as rashes and inflammation. Often, any reaction experienced is non-allergic and can be resolved or prevented by following our wear and care guidelines.