made with cast iron, and good quanlity,colorful rubber dumbbell material:cast iron Process technique:RUBBER Available Weights: 1KG,2KG,3KG,4KG,5KG,6KG,7KG,8KG,9KG,10KG,12.5KG,15KG,17.5KG,20KG----50KG PACKING:1pcs / Polybag 1pcs / 1ctnabout 1000kgs /case 20'GP:22000kgs RB-103 rubber dumbbell