This is the insulator for the horn contact for the Ford models below.
It pushes into the steering wheel, and is often missing.

Fits:
1958, 1959, 1960, 1961, and 1962 Fairlane/Galaxie
1959 and 1960 Edsel
1961, 1962, 1963, 1964, 1965, 1966, 1967, 1968, 1969, 1970, 1971, 1972, 1973, and 1974 Econoline
1961, 1962, 1963, 1964, and 1965 F-100/250 4WD
1966 F-250 4WD
1961, 1962, 1963, 1964, 1965, and 1966 F-350/1100