Here are the specifications for this zinc:
Mounting Holes: 50mm (2") center-to-center
Weight: 0.80 lbs
SKU:DF-107
US Military Grade Zinc Anode.
If you need to investigate this zinc application or location, you may visit the assembly and operating instructions for the Variprop DF/GP-80 and DF/GP-107 2-, 3- and 4-blade model