"Knee Actions" were only installed on passenger cars. They were a pod shopped device which functioned as both a spring and a shop absorber. They were first installed on the 34' year model (I think) on the master series. They were continued on the master series through the 1938 production year. The 1939 year converted to front coil springs. They were also available on Pontiacs 1934 through 1936.
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