You are looking at a pair of upper door trim mouldings for 1973-1987 Chevrolet and GMC pickup truck and 1976-1991 Blazer and Jimmy.

These are made of black ABS plastic but can be painted to match your truck's interior. 

These install above the door at the headliner and connects between the front and rear pillar posts to help secure the headliner. Fits left and right sides.

Please see sellers other listings for sets of front and rear interior moldings.