2 gentle uses SHARKBANZ 2 Magnetic Shark Repellent Band. One black and one white. Good for Swimming, Surfing, Diving, Snorkeling and Surfing All Ocean Sports. Each retail for 177$ in Amazon. Can wear on wrist or ankle. From website: The world's first active shark deterrent band. Designed for beachgoers, swimmers and surfers, Sharkbanz use patented magnetic technology developed by marine biologists to deter predatory shark species. EFFECTIVE - Technology based on proven science, published research and testing No batteries, no charging; always on. STYLISH - Ergonomic design and premium materials for enhanced comfort Worn on Ankle or Wrist Universal. Weigh 85g. EFFECTIVE SHARK DETERRENT - Using patented magnetic technology, Sharkbanz overwhelm sharks’ electroreceptors causing a highly unpleasant sensation that turns sharks away. Technology based on proven science, published research, and testing by the Western Australian Government and verified by an independent third party University. No Batteries, No Charging; Always on. Lightweight (3 oz). Wear on your ankle or wrist. Waterproof to 100M / 330 ft. TSA and Airline Travel Friendly. Magnetic Shielded Box included for safe storage. Universal Fit, Ages 5+. PREMIUM MANUFACTURING - Ergonomic design and premium materials used for enhanced comfort and durability, including soft silicone band and stainless steel Sharkbanz can be worn over or under wetsuits and will not affect ocean athletic performance.