173 2-1/4" Ball Mount for Fishfinder & ChartplotterFeatures: The Scotty 2.25a ^2 Ball Mount enables anglers to mount larger fish finders on their watercraft; It's designed for 10a ^2-12a ^2 fish finders and offers sturdy and secure holding power; Prefabricated holes on the top plate allow easy installation gimbal mount brackets that come with anglers' fish finders; Produced using corrosion proof reinforced nylon; - cis2:mm5mnJlm -Brochure (pdf)