Training ball for baseball and softball batting practice
作者： Scott Stebbins
DOI:
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摘要: A weighted training ball for baseball and softball batting which has a solid body of molded elastomeric material regulation circumference between approximately 9-16 inches. The is to have greater than weight 7.5-20 ounces. also softer baseballs softballs, with type A-2 Shore durometer 40-70.
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