Standard Special model
Made 1937 - 1943 (Sernr 122### - 143###) Classification: Semi-Professional
These horns seem to be based on the Handcraft Committee model.
I do not know why they are called Standard Special. I have not seen engravings yet with the addition "Special".
But since they are not the same as the "Standard" model, I guess "Standard Special" is a valid name
The fact that these horns where produced at the same time as the Handcraft Committee and Committee 2 combined with some cheaper details (fixed right thumbrest, no heartshaped left thumbrest) makes me think these are somewhat watered-down versions of the Handcraft Committee.
This model does not have the Eb vent key, below the low D key that the "Standard" features.