Ford model 2100 carburetors were used on Ford, AMC and Jeep from 1957 to 1980. Model 2150 was similar and was used from 1974 to 1992.
The 1957 (first design) Ford 2100 was quite different from later models, notably using a much longer accelerator pump stem than later models. The second design appeared in 1958, and with minor changes was used on Fords until 1974 and AMCs until 1980. The illustration above shows the 1958 design.
Ford 2100 carburetors are marked with the venturi area in inches cast into the driver's side of the float bowl. These range from about 1.03 to about 1.25 square inches.
Ford carburetors are generally identified by the number on a metal tag. The carbs are variously marked as Ford, Autolite or Motorcraft depending on the year of manufacture. Model 2100 carburetors were also stamped with part of the carb number on the edge of the base, near the front on the throttle body.
Ford tags and stamps are discussed here.
The 2100D version added a choke pull down diaphragm behind the choke plate.
Model 2150 was a further revision using a separate, external choke pull off.