The TRIANG HORNBY OO Gauge X391 SYNCHROSMOKE SMOKE UNIT is a vintage smoke unit designed for model railways in the OO scale. Made of white metal by the renowned brand Hornby in the United Kingdom, this analogue control system unit is compatible with Princess, Battle of Britain, and Britannia models. The smoke unit is powered by DC and is a unit type accessory for enhancing the realism of railway layouts. Ideal for collectors and enthusiasts looking to add a touch of authenticity to their model railroads.