Durable plastic pieces fit together to create a wavy design for added balance challenge. Raised, tactile texture for more traction on top and full-rubber slip-resistant bottom for added safety. Stackable for easy storage and transport. Includes storage bag. Set of 8 beams, each 26"L x 7"W x 4-1/2"H; 27 lb (66 cm x 16 cm x 11 cm; 12.25 kg).