Trumark ® Steel-Ball Ammunition has been selected for it’s special size; it’s not too small and it’s not too large. Ammo that is 1/4" or smaller is too light and will "tear up" wrist braced slingshot bands that need more weight in the pouch when shot. Steel ammunition that is larger than 3/8" is too heavy and unsafe if used improperly. Trumark’s ammo is a good balance between light and heavy, and is the ideal size for shooting in all wrist-braced slingshots. Perfectly round Trumark's, Grade A ammo feels good in the pouch, and lets you concentrate on the target as you get ready to shoot. Grade B ammo has a "flat spot" that is found on cheaper metal balls designed for mixing paint in spray cans. Avoid paint-can balls. Always shoot Grade A Trumark® 5/16" steel-ball ammo for BULL'S-EYE accuracy! 120 Shots per bag.