When I was at Cabela's the other day they has this big plastic board, I guess the best way to describe it is that it looked like a cutting board. It was like 12" long and maybe 6" wide. All it said was that it was for mounting the tranducer. I saw somewhere about someone using one of those plastic type cutting boards and making their own.
So this question is why do you use one of these.
So this question is why do you use one of these.