A 13" tall, 1 1/2" diameter, brushed aluminum, non-threaded post with a steel pin.Attwood's 3/4" pin pedestal design uses patented Lock'N Pin technology for safety and versatility. Drop-in components easily slide together, then lock” into place to prevent unintentional detachment.Key FeaturesLock' N-Pin prevents unintentional detachment for seat mounts, posts and basesLock' N-Pin products exceed ABYC Standard H31.6.1Type B rating, not to be used as a helm seat, for speeds not to exceed 5mphMade in the USA