Marine seat base Pneumatic/manual aluminum alloy anti-corrosion and anti-rust seat base bracket

Marine seat base11053/11063 It is a manual seat11083 It is a pneumatic seatAdjustable range:11053/11063: Minimum 13 inches /330.2 mm, maximum height 18 inches 457.2 mm11083: Minimum 14.5 inches /360.8 mm, maximum height 20 inches 500.8 mm(Pure manual measurement, there is 1-2 cm error, please refer to the actual object)The boat seat allows you to sail smoothly through rough seas and huge waves. Aluminum base, with rust and corrosion resistance, adjustable hole position and height, shock absorption, gas drive, durable, UV and salt water resistance, easy to install,