Chairs stamped with a clean, 6-digit number (e.g., 161985 , 161986 ) appear to represent an earlier manufacturing phase.
If you cannot see a number immediately, check these standard locations: Underside of Seat:
🧼 Clean with mild soap and a soft brush – paint often hides numbers.
If your chair has a serial number over 100,000 (e.g., 109877), it likely dates to the late 1920s or 1930s.
| Feature | Introduced | Discontinued | |---------|-------------|----------------| | Hand-crank elevation | 1890 | ~1910 | | Hydraulic foot pump | 1905 | 1970+ | | Porcelain armrests | 1912 | 1940 | | Tufted upholstery | 1915 | 1950 | | Chrome plating (trim) | 1928 | 1965 | | One-piece streamlined back | 1935 | 1960 | | Foam cushion (no tufting) | 1952 | 1968 |
: The most frequent location, stamped on the underside of the wood or the metal seat frame. The iron base casting
If the serial plate is missing, use these :