Pair of brass-toned keys with numeric stamping

The image displays two matching keys, likely constructed from a copper-based alloy such as brass or a similar metallic material given their yellow-gold coloration. Each key features a circular bow with a rounded cutout at the top for attachment to a ring. The flat surface of the bow on both items bears a horizontal stamped numeric code reading "3104". Below this code, stylized horizontal lines are etched into the sides, which is consistent with decorative motifs found on mid-to-late 20th-century hardware. The blades appear to be of a standard tumbler lock variety with specific notched biting patterns along the edge. The surfaces show minor scuffing and oxidation consistent with previous use and age. There are no legible manufacturer names or brand logos visible, though the design is stylistically consistent with utility keys used for small-scale locks, such as those found on cabinets, padlocks, or older automotive components. Without a maker's mark, the origin and specific application remain unverified and are based on general physical characteristics.

Based on my visual examination of the provided image, I have evaluated this pair of brass-toned keys. The items appear to be mass-produced utility keys featuring a '3104' stamp and standard tumbler biting patterns. From what I can see, the metallic composition is consistent with a copper-based alloy, though I cannot verify the exact metallurgy or age from a photo alone; physical testing would be required to rule out modern plated simulations. The design, including the horizontal decorative etching, suggests a 20th-century origin, possibly for a cabinet, padlock, or automotive use. The value estimate of $5.00 to $15.00 is based on the assumption that these are functional vintage hardware pieces. In the general market for such items, demand is typically limited to collectors of locksmithing ephemera or individuals seeking specific replacements for older locks. Condition issues like visible scuffing and oxidation are common for utilitarian objects of this type and are accounted for in the estimate. To confirm a more specific origin or application, an in-person examination by a hardware specialist or the discovery of provenance linking them to a specific manufacturer would be necessary. Should these be determined to be common modern duplicates rather than vintage originals, the market value would likely drop to a nominal replacement cost of $2.00 to $4.00.