8 PACK-Fence Post Plastic Black Cap 4x6 (3 5/8" X 5 5/8") Pressure Treated Posts Fence Post Plastic Black Cap 4x6 Pressure Treated Posts CAP PRESSES OVER THE OUT SIDE OF A 4X6 POST EXACT INSIDE DIMENSION OF THIS CAP IS (3 5/8" X 5 5/8") MADE IN THE U.S.A. Free Shipping