Kingsdown Antiques has dated this piece to the 1910s.

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Measurements:
Sandwich box height: 1 1/2" (approx 3.75cm)
Length: 5 3/4" (approx 14.5cm)
Width: 2 3/4" (approx 6.75cm)
Flask length: 6" (approx 15cm)
Width: 2 3/4" (approx 6.75cm)
Leather case height: 1 3/4" (approx 4.5cm)

Length & Width: 6 1/2" (approx 16.25cm)
Total weight: 1471g
In good condition - any dark areas are shadows from the photography, there is no damage to the silver plate or glass, however the silver top of the flask has a couple of small dings (consistent with age). The leather is also in good order.
Kingsdown Antiques has dated this piece to the 1910s.
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