2-7/8" Heavy Duty Mainstay with SwivelNon-removable pedestal system in 2-7/8" offers a heavy-duty base and post for today's larger and faster recreational boats. The base is permanent mold AC7A aluminum alloy with an anodized finish for maximum strength and corrosion protection. Then a 2-7/8" heavy-duty extruded post is pressed and hydra-formed into the base mechanically forming them together. This proprietary process allows maximum strength for a sturdy pedestal.Features:2-7/8 in. pedestal with 9″ round baseRigid 4-keyed aluminum post, anodized finishAir-powered height adjustmentAdjusts (inches) 14" to 19.5"Warranty: 5 years