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These black trim strips cover the edge of the gutter on the roof or the drip rails on the front next to the windshield (A-pillar) of your T3 Vanagon. Left and right strips for the front are different. There are two different end pieces for the gutter trim strip (4 in total). Like the bumper ends they fit front left/right rear and right front/left rear respectively.
For a whole set you need 2x gutter strip, 2x end piece LF/RR, 2x end piece RF/LR, 1x drip strip left, 1x drip strip right.
Part Numbers: 251853707D, 251853705, 251853706, 251853709, 251853710