Allen, R.C.
				R.C. Allen, Business Machines Inc., New York, U.S.A.
Models and s/n	Y	M	D	Remarks	Ref.
Model 600
up to 1120000	1950				15
1145000	1951				15
1166000	1952				15
1176000	1953				15
Model 700
up to 1750000	1952				15
1768000	1953				15
1820000	1954				15
1850000	1955				15
2100000	1956				15
2139000	1957				15
Model 800
1920000	1957				6
1980000 to 2029999	1958				6
Model 'A' Visiomatic
2030000	1959				6
2100000	1960				6
2200000	1962				6
2300300	1963				6
2330800	1964				6
2350400 to 2358399	1965				6
Model 'B' Visiomatic
2358400	1966				6
2367200 up	1967				6