Are you buying new rubber for the whole Pickup well its hard to forget about the door window sash rubber. This particular piece fits into the sash which is located at the bottom of your door glass to keep your window from rocking back and forth and possible damaging it. These are sold individually and will need one per door on your Fullsize Chevrolet or GMC.
Years Fit Fullsize C & K Series 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987