This set of Flat Spot Markers by Uber Soccer are made of non-slip rubber that offer a great training aid for all types of sports training drills. They are suitable for indoor or outdoor use and will stay firmly planted in place when underfoot. They come in a durable Nylon-Mesh Transport Storage Bag that has a mesh side for moisture control. Each spot marker is 8 inches in diameter. These high-quality rubber flat spot markers come in 4 colors (White, Yellow, Blue and Red) or 5 of each color to make a complete set of 20. Perfect for soccer, tennis, football, la crosse, field hockey, track and field and more. A great training tool for coaches, trainers and sports teams. Use anywhere a cone can't be used.