Beautiful seam, and spiral reinforcement adopted, preventing the burst in boxing. Empty sandbag and zipper seal, easily to adjust the weight of the bag when filling. You can DIY! Three bolts on each side to reinforce, good drapability and stability with strong weight bearing capacity. Made of durable canvas cloth, and well welded iron chains, greatly ensuring the safety of sandbag after . A great workout tool for stress relief, weight loss, self protection, enhancement and sensitivity and responsiveness improvement. Specification: Color: black Material: imitation leather and canvas cloth Diameter: 15.75in/40cm Length: 47.24in/120cm Package Includes: Package Includes: 1x Punching Bag (Empty); 1x Iron hanging chains; 1x Hanging buckle; 1x Hanging Hook Note: Recommended fillers: sawdust, used clothes, rags, corns, grain, coarse cereals and etc. Please do not add too much sand, because most sand is wet, and it is easy to be blown even if it is dry.