| 摘要 |
In applying to an externally threaded bottle neck an unthreaded metal closure having a gasket within it, the closure shell is pressed down on the bottle and while the shell is so held the diameter of the upper end of the skirt is reduced at angularly spaced intervals to press the gasket into sealing engagement with a cylindrical sealing surface on the neck of the bottle above the bottle thread and simultaneously to form a band of knurling which can be grasped manually.
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