This Martyr CMX11 anode is the perfect addition to your outboard engine. With a streamlined design and a 2-1/2 inch diameter, it provides superior performance and durability. Made of high-quality zinc, it is built to last and withstand the rigors of all types of marine environments. The anode is designed for easy installation and is compatible with a variety of outboard engines. It is a must-have for any boater looking to improve their vessel's performance and protection.