The height mechanism in this pedestal is automatically adjusted. The pedestal's base is 2 3/8" in depth, but its top is wider to allow the seat mount. The adjustment handle is positioned on the mount allowing access from the front side. Three degrees of tilt are offered by the base. All seating accessories from the 238 series fit the unit. The seat post is made of stainless steel and has a durable black powder-coated finish. Attwood 238512-4 is one of the most reliable boat seat pedestals on the market. Technical Features: 1. 19.5" to 23" adjustment 2. Hard-anodized aluminum 3. Forward Handle 4. 3° Tilt. PROS🟢 Sturdy construction Simple design CONS🔴 No way to add extensions