| 摘要 |
Exterior radial or tangential openings are cut or molded within a bowling pin base insert which permit the exterior plastic coat during the injection molding process to flow into such openings and, upon hardening, form a tight and rotationally secure locking arrangement between the base insert, the exterior plastic coat and the wooden pin core, said bowling pin base insert having an interior annular recess to provide expansion space for the bowling pin wood core.
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