1975 - 1986 Chevrolet K20 Rear Window Weatherstrip Seal, With Trim Groove For Lockstrip For Lockstrip. This rear window seal goes first on the body then the glass is placed in the opening. Tucking in the self locking strip secures the glass in place. Made from ozone resistant EPDM rubber and from the same OE specs as the original for an authentic fit and finish.