Leeds Antiques has dated this piece to the 1920s.
The upholstered burgundy coloured leather hide seat is trimmed with brass tacks. The seat is supported by the height adjustable, tilting and swivelling, patented mechanism. From which protrudes four legs on ceramic and iron castors.

The mechanism adjusts for height by way of a collar around the threaded stem, the tilt springs tighten by way of a wheel to restrict the level of incline, and the swivel tolerance can be adjusted by way of a nut.

In very good condition, serviced, cleaned and waxed, all working and ready for use.
Dimensions:
This chair measures approximately 89.5 cm (35.25") tall at minimum height, at which the seat height is approximately 45.5 cm (18"). The height can then be adjusted up a further 6 cm (2.36"), or possibly even a little more, and therefore adjusts the overall and seat heights accordingly.

The chair width is approximately 58.5 cm (23"), and has a depth of 62.5 cm (24.5"). The seat width is 47 cm (17.5") between the arms, and 44.5 cm (17.5") deep from the front edge to the back upright.
Condition:

Please see the pictures for details of the items condition. - This chair is in a very good overall condition. There are some odd marks and blemishes on the frame. The upholstery appears original and is in a very good condition considering. It is nicely worn in without being tired. There is a very small bit of fill in a chip on bottom of the left arm, where screw holes have been plugged. The mechanism has been fully serviced and works well, with all aspects functioning. The chair has been cleaned and waxed and is very much ready for use. - As with all vintage & antique furniture there will be signs of use, marks, wear & tear, etc.
Leeds Antiques has dated this piece to the 1920s.
Second-generation antique dealer specialising in carefully sourced 17th–20th-century furniture and décor, chosen for quality and character.
You can view the stock and full dealer information on the Leeds Antiques Profile Page