7"x7" square stainless steel base SP-69773. Easy to install with six screws or bolts through the deck. Add more seating to your pontoon, fishing or cruising boat with Attwood seating products. Attwood Corporation has been an award-winning leader in engineering, testing, and manufacturing the highest quality marine products for over 100 years. We deliver safe and reliable lighting, fuel systems, water systems, seating & pedestals, swim ladders, custom upholstery, and general marine accessories that are easy to install and meet regulatory compliance.