You are looking at a new old stock American Motors bumper plastic trim piece. This will fit on the rear bumper (right side) on the 1977 thru 1980 AMC Pacer. It is a hard plastic piece mainly intended to keep the bumper from getting damaged in minor collisions. I dont think you will find may of these around. This one is from and old AMC dealer’s stock bought years ago.
armrest box
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