The Lizars Challenge Stereo Tropen (Tropical) is an early 20th-century tropical-finish stereo plate camera, built for paired side-by-side exposures. Tropical-bodied examples of this type were produced in teak or polished hardwood with brass fittings, intended for use in hot and humid climates where standard leatherette-covered bodies degraded.

Sales data for this model is extremely thin: a single recorded UK auction result from Christie's in 2002 shows a hammer price of £1,410 at saleroom level (wholesale, excluding commissions). With only one verified data point — and one more than two decades old — there is no reliable current market range, and what a Lizars Challenge Stereo Tropen is worth today in 2026 depends heavily on condition, completeness of original lenses and plate holders, and the integrity of the tropical woodwork and brasswork.