Screw on closures are the most common bottle caps. They are easy to apply by a wide variety of automated equipment, or they can be applied by hand. The application torque of closures however must be controlled in order for the closures to perform properly in the field. Closures must be applied tight enough to maintain a seal and to resist closure back-off, but must be not be applied so tightly that the end user cannot remove the closure. They are often found on top of beers, such as Coors or Dos Equis.
Screw caps were originally an internal thread design. A glass bottle / jar with an internal screw-thread immediately below a gasket-seat, having a beveled seat, was patented by Hyman (Himan) Frank of the William Frank & Sons, Inc. of Pittsburgh, PA. He was awarded patent US 130208 A on August 6, 1872.
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