7" x 7" LOCK 'N-Pin 3/4" Pin Base is aluminum. It features an acetal bushing for secure fit and durability. 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.