Product attributes: It contains steel balls for slingshot ammunition in 4 sizes. They are 1/4,5/16,3/8, and 7/16 in diameter, with 100 of each size. There are 400 in total. Product advantage: The design is designed to satisfy buyers' needs for different types of shots. When shooting at different prey, you can choose different sizes of steel balls.It can also be used as an experiment to help you choose the best size for you by experimenting with different sizes.