Nuvo Iron Decorative Pineapple Post Cap for 3.5" x 3.5" Posts, Black - PCP04 PINEAPPLE POST CAP - Nuvo Iron black aluminum pineapple-shaped cap for fence posts. ORNAMENTAL - Top the perfect fence with stunning ornamental black aluminum for a classy look. PROTECTION - Marine grade architectural designed aluminum post caps add value and protect top of posts. For 3 1/2" x 3 1/2" posts. DIMENSIONS - Square pineapple post cap: 4 x 4 x 7.5.