This is the first camera with a coupled rangefinder. Several lens/shutter combinations were available, this example was produced for the UK market.

J.E. Woodbury's patent of 1914 (BP 13421) seems to be the basis for the rangefinder fitted to the 3A Autographic Kodak Special of 1916 where the arrangement was simplified by fitting a narrow wedge in place of the lens combination shown in the patent. In the original patent, as shown on the right, two fixed mirrors are used. The image from one is deflected by a small amount by a lens combination, in the neutral position the deflection produced by the lenses is zero. The positive part of the lens combination remains fixed to the baseboard, the negative lens (and mirrors, camera lens, front standard etc.) move forward and back along the baseboard so altering the deflection produced by the lens combination.