This Attwood Sure-Grip Rod Holder Mounting Base provides a solid, reliable mounting point for a Sure-Grip Rod Holder (sold separately). This flat rail base is designed for mounting on a square rail. It is made of extruded aluminum and is pre-drilled for secure mounting. Attwood Corporation has been an award-winning leader in engineering, testing, and manufacturing of 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.