A classic training accessory, Sportsmith medicine balls can be used in a variety of exercises to build coordination, strength and endurance. Perform circles, twists, figure-eights and more to strengthen arms, shoulders and back, develop powerful abs and improve core stability. Use during squats, lunges and reaches to build leg strength and explosiveness. Use the medicine balls alone or with a partner for a variety of exercises. Set includes five popular sizes � 1kg/2.2 lbs., 2kg/4.4 lbs., 3kg/6.6 lbs., 4kg/8.8 lbs. and 5kg/11 lbs. Each inflates with standard sports ball pump to desired bounce. Solid weighted core. Textured surface enhances grip.