Alpina
Models and s/n	Y	M	D	Remarks	Ref.
Portable
up to 1600	1951			Serial numbers run through all models	13
5200	1952				13
5201-7600	1952			New models	13
up to 18800	1953				13
39100	1955	Mar			6
58100	1956	Mar			6
73700 onwards	1957	Mar			6