This is the electrically heated version of the D16. It is also available in a tablet heated version. It is a typical Wilesco mid-range engine of something like 1970s vintage. A good looking engine with a double-acting cylinder, utilising the characteristic "piston" valve driven off a slip eccentric for reversible running. A dummy governor, consisting of a pair of free swinging balls, is mounted on the engine base-plate, driven by a belt from the flywheel.
The heat source is a 220 V 300 W electric element, strapped underneath the boiler. Steam is supplied to the engine via a needle valve throttle and an in-line lubricator. The feed pipe is routed down the side of the boiler and under the base plate to the throttle. The exhaust from the cylinder exits by a short pipe to a drip-tray fitten into the base.
The boiler, 55mm diam. x 130mm, has a circular glass window in the end for indication of water level, a typical Wilesco (rather fancy looking) combined whistle & safety valve (weighted) and a second safety valve (spring loaded). The boiler is mounted on a brick-effect firebox with typical Wilesco decorations. The chimney is purely decorative; not even the steam exhaust goes up it.