One of the many 16 on VP size roll-film cameras produced around this time, the Derby is unusual in having a focal-plane shutter. It was a very popular camera and sold for about ⅓ (£5.8.6) of the equivalent Leica. Several models were produced with further minor variations.

• The original Derby, introduced in 1930 or 1931, took 36 x 24 mm exposures on 127 roll-film. The finder was either a large folding type, or enclosed tubular form.
• The second model (1931) took 4 x 3 cm exposures on 127 roll-film. Both types of finder were fitted.
• Around 1934 delayed action was added and the fastest lens available was f2.5 rather than f3.5. Following the delayed-action change, an extra pair of film advance windows were added, the original red windows were suitable for orthochromatic film the newly added green windows were for panchromatic.
• Around 1937 existing models were designated Model 1 (in some advertising) and a new version - Model 2 - was introduced having interchangeable lenses.
• Around 1939 a rangefinder version was introduced by Foth in Paris. A rangefinder option was also available from the American distributors.