The Vintage Wrist Watch Company has dated this piece to the 1910s.
The chain measures 35mm long including the T-bar and the clasp.
The T-bar is unhallmarked, but has tested as being silver, it is probably a later replacement.
The clasp is hallmarked for 1913, with Herbert Bushell’s initials.

The chain comes with a silver gymnastics fob, hallmarked for Birmingham 1913 with a maker’s mark for the fob manufacturer Joseph Daffern of Hatton Garden. The fob is free of any personal inscriptions.
Total weight 43g.
The Vintage Wrist Watch Company has dated this piece to the 1910s.
Specialists in antique and vintage wrist watches and pocket watches
You can view the stock and full dealer information on the The Vintage Wrist Watch Company Profile Page