Differences:
The 960 was the commercial version of the 160 in Europe. It took over from the 925 in 1938-39, then was made post-war 1947-48, before being replaced by the 912 in 1949.
In the US, you had the Model 90 after the 925, I believe.
The only differences between the 160 and 960 were that the 960 had a larger bag (for the filtering of a greater volume of office or hotel dirt!), a lined fan-chamber (see above!)and an all-white headlamp reflector plate, rather than the half-white, half-black one on the domestic 160.
Oh, and they did away with the fabric bag strap, using a spring instead - although I don't know if that applies to all models, or just post-war models, as I don't have any information about the pre-war 960s.
21,941 of these machines were built over a two year production run, from January 1947 to July 1948. My particular example dates from March/April 1947, making it an early-ish post-war example.
