Model L1233
…...signifying ; luton built model 12 of 1933. The year the flip over carpet nozzle was first produced. The 12 was introduced in 1930, had a black body covering and the old pattern one piece non swivel elbow carpet nozzle. I know that by 1933 it would have cost 18 guineas (probably the highest priced cylinder cleaner on the british market) lux named it 'THE GREATER ELECTROLUX' as it superseded the model 11 (1926-30, first produced at luton when the factory was built in 1927. The 11 was described as 'HAVING AMPLIFIED SUCTION' over the previous 'pistol grip' model 5: sleeve bearings requiring regular oiling. (1921 till circa 28/29?) ; the 11 was the first true cylinder produced by lux and was fitted with ball race bearings. Model 11 had smaller diameter hose, tubes, body size and non swivel 'hose to machine connection'.
The 12 was the same wattage as the 11 but had larger motor components and larger fans greatly improved and scientifically endorsed rear filter cartridge.
The higher powered model 25, with tapered hose and other features as the deluxe model in 1934.
The 12 was replaced by the now rare 18 (1934-5) as the mid range model.
Hope above info is helpful.
Regards, Walter (fellow scot) Shropshire, WEST MIDS.