In 1902, Conrad Hubert received a patent for the first flashlight with an on/off switch in a cylindrical case.
With the development of smaller, more powerful “D” cell batteries, it became practical to carry a hand-held battery-powered torch or “flash light”, so called because the battery was only able to sustain light for a few seconds. Hubert’s business, American Electrical Novelty and Manufacturing Company, marketed flashlights under the Ever Ready brand name, and eventually became the American Ever Ready Company.
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