Vintage Federal Law Prohibits Sale or Reuse of this Bottle Whiskey Flask

This is a vintage clear glass institutional whiskey flask, easily identified by the embossed 'Federal Law Prohibits Sale or Reuse of this Bottle' warning typical of post-Prohibition era containers produced between 1935 and 1964. The bottle features a characteristic square base with rounded shoulders and a classic machine-made construction. The glass exhibits a slight greyish-green tint common in mass-produced mid-century utility glass. The base shows a complex maker's mark consisting of embossed circular text and numerical codes, likely including a plant code and date code from a manufacturer such as Owens-Illinois, though the specific center logo is partially obscured. The physical condition appears fair to good; there is visible surface wear, internal residue ('clouding' or 'sickness'), and several scratches on the bottom surface which are expected with age and use. The embossing is well-defined, showing the sharp detailing required for federal compliance during its tenure. Standard bubbles within the glass and mold seams running up the sides of the square body are visible, confirming its origin as an industrial mid-20th-century piece of American glass manufacturing history.