Kingsdown Antiques has dated this piece to the 1920s.
The case has a strap for ease of carrying and this box was probably for equestrian use - circa 1920.

Measurements of Silver Plated Sandwich Box:
Height: 3 1/2" (approx. 9cm)
Width: 6 1/2" (approx. 16.5cm)
Depth: 1 1/2" (approx. 4cm)
Total weight of Box and Leather Case: 610g
In good condition – Light surface marks and signs of gentle wear, consistent with age and use. There are no dents of repairs.
Kingsdown Antiques has dated this piece to the 1920s.
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