The Adjustable Lock'N-Pin 3/4'' Pin Post features the Lock'N-Pin system that prevents unintentional detachment for seat mounts, posts and bases. This brushed aluminum post has a power adjustable height that adjusts to height of 15" to 18". The Attwood(R) Adjustable Lock'N-Pin 3/4'' Pin Post is non-threaded and has a 1.77" diameter. FEATURES: Brushed aluminum Lock'N-Pin system prevents unintentional detachment for seat mounts, posts and bases Power-adjustable Non-threaded Steel pin Height: 15"-18" Diameter: 1.77"