Martyr Large Bolt On Hull Zinc Anode 8-1/2" x 3-5/32" by Martyr $51.69 SKU MTRMZ406 1 2 3 4 5 6 7 8 9 10+ Quantity Quantity Add to cart LENGTH: 8-1/2" WIDTH: 3-5/32" HOLE CENTER: 1/2"