• 3 1/2 in. streamlined inboard propeller shaft anode
• Zinc alloy for boats in salt water environments
• Martyr anodes are made of a high purity specialized alloy based on the US Mil Spec
• Secures to prop shaft with 2 interlocking halves and allen head bolts with bolt retaining washers
• 3 1/2 in. inside diameter
• 5.7 in. outside diameter
• 3.78 in. height