Waterhouse Camera Stops (Set of 8)

A small brown leather case with a tuck-in flap for set of 8 Waterhouse Stops. Inside of front case flap is embossed in gold: 'WRAY | LONDON'. The copper alloy Waterhouse stops has varying hole sizes, these are numbered accordingly.

There are 8 Waterhouse stops but one does not appear to be part of the set. The copper alloy Waterhouse stops are marked - one is stamped ‘10’, the others have white embossed marks front and back:

1) Front: f/5.65, Reverse: 2

2) Front: f/8, Reverse: 4

3) Front: f/11.3, Reverse: 8

4) Front: f/16, Reverse: 16

5) Front: f/22.6, Reverse: 32

6) Front: f/32, Reverse: 64

7) Front: f/45.2, Reverse: 128