Sinclair resurrected the name they had used in the early part of the century for the last development of their Una hand camera.

The original notices of the camera stated: 'Messrs Sinclair have done an exceedingly good thing for travelling in tropical countries by making available the highly efficient Una camera in a model which eliminates the inevitable risks of even the best seasoned wood in camera construction. Throughout, the mechanical construction of the camera is of the highest. The price, inclusive of three double plate-holders, is £35.'

By 1940 the camera was being targetted more precisely, at an increased price of £45: 'The Traveller Una is built on the same lines as our Standard Model and is particularly suited for Explorers and Scientists who require an instrument to stand the roughest wear and tear. It is made of Duralumin - a metal nearly as light as aluminium but without its drawbacks, and its beautifully finished. It is adapted for hand as for stand use, and the Ross Combinable lens fitted is perhaps the most generally useful lens made for the practical worker'.