Review on Speed Hound Marathon Swim Buoy: Ultimate Open Water Swimming Buoy 🏊 and Flotation Device with Dry Bag - Ideal for Triathletes, Swimmers, and Snorkelers! by Bob Vulpes

This is a good choice for two main reasons: (1) it's a canvas/plastic material, which is more durable than regular thick plastic versions; and (2) it is a bright orange color that is very easy to see during a foggy morning swim. (Sometimes we even threw in a bike turn signal early in the morning and it lit up the whole bag like a beacon so the early morning ski boats would see you clearly. Seals well but mine broke after a few uses. So a double seal freezer bag is might be a better choice if you have things that really mustn't get wet).