作者: Donald Spector
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摘要: A child's play ball constituted by an outer casing and inner inflatable bladder. The is formed contoured segments of high strength, non-stretchable fabric material stitched together to define, when the fully expanded, a desired shape size, such as football or soccer ball. bladder conventional rubber balloon whose stem initially projects through opening in which provided with closure. stem, after inflated air so that it conforms casing, then tied retain air, being concealed within maximum safe diameter well below at close its bursting point, approximately equal dimension expanded whereby encased has exceptional strength may be subjected rough handling.