These bags come in four sizes. All sizes are measured in open diameter. The size of the bag needed is dependent largely upon the size of the boat, the speed of the boat, and how slow you want your boat to go. The following measurements are just a guideline.
The 15" and a 18" open diameter bag is designed for fishermen who have 16' to 19' boats that troll too fast. Instead of putting one 22" bag down, you can get the same results from running two smaller bags, one on each side. This will make steering much easier
The 22" bag is used on boats from 14' to 24' .
The 28" bag is used on boats from 24' to 30'.
Priced per bag | 
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