Most bigger units with side imaging will also have down image and GPS . There are some small units with all the bells and whistles but bigger screens easier to see . BBG Marine a sponsor on here has lots of options at great prices . I started out with handheld GPS and a cheap sonar both under 100 bucks each . But since upgrading several times to 10'' screen with all the bells and whistles I would replace it if it were gone and I am ordering another 10'' screen for the bow of my boat now .
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Takeum Jigs