This is the pre-war version of the SE2. It appears to be one sold under the Hobbies brand. It was acquired along with a Hobbies branded box and the paint colours are consistent with the Hobbies version. The pre-war version of the SE2 (like the others in the SE range) was somewhat different from the post-war version. It had no exhaust throttle but was fitted with a reduction gear to a counter-shaft. It was also somewhat smaller than the post-war version.
The boiler is 1 3/4" diameter x 4" long. It has a safety valve and water level plug but no whistle. The chimney is mounted on the boiler and it receives the exhaust from the engine. There is no steam dome, just a compression joint to the steam feed pipe. All other pipe connections are the same compression fitting.
The steam feed goes directly to the back of the engine frame, with no throttle or inline lubrication. The engine frame is cast brass and has bearings for the crankshaft and countershaft.
The engine is a single oscillating cylinder, 5/16" bore x 1/2" stroke. The piston rod is connected to a 1 3/16" diameter disk crank, which also serves as a flywheel. On the other end of the crankshaft is a small pinion which meshes with a larger gear wheel on the countershaft, giving a 3:1 speed reduction. The countershaft has two pulleys of different sizes for belts. I'm not sure if both these are original. The only provisions for lubrication are a hole drilled into the crankshaft and countershaft bearings.
It was all in working condition as acquired; all it needed was lubrication. It came with a much damaged meths burner but I don't think it was original anyway. I have replaced it with a similar one in better condition. The disk crank looks suspiciously new so I assume it has been replaced.