The adjustable hoop plastic toys of the adjustable hoop is hollow,so if you need to increase its weight, you can add sand or stuffing to adjust the weight of the kid sport hoop bulk .Of course, you can't add to much weight too Exceed the load of the kid sport hoop, otherwise the adjustable hoops are very easy to fall apart, in addition,the ends of each kid sport hoop piece are not open,if you add the sands, it can ensure uniform force.