Upgrade or expand your boat seating with the Swivl-Eze Lock'N-Pin 1.77 Series Aluminum Snap-Lock 9-Inch Boat Seat Round Base Plate. This durable base plate provides a secure and reliable foundation for your boat seats, making it ideal for fishing, pontoon, or cruising boats. Designed for easy installation, it can be used as a replacement for existing systems or to add an additional seating position. Constructed from hard anodized, corrosion-resistant aluminum, this base plate is built to withstand the harsh marine environment and provide long-lasting performance. The 9-inch round design offers a great balance of value and functionality. It requires a 2.5-inch diameter mounting hole for installation. Swivl-Eze marine products are engineered and rigorously tested to ensure worry-free boating under all conditions. The snap-lock mechanism allows the seat to securely lock in any swiveling position; providing convenience and safety while on the water. This plate is designed to provide a stable, rotating seat base for comfortable and efficient boating. The aluminum construction ensures resistance to wear and tear, promising years of reliable use. Ideal for both fresh and saltwater environments; this base plate can withstand the elements. Compliant with industry standards for marine applications.