Which transducer do I need?

I just bought the hummingbird 363 ff/gps, I see that there is a transducer exchange program and I own a OK T-15, and I'm a newbie so I want to get it right. I'm assuming I want the throughout transducer, but one is bronze and the other is plastic, It came stock with the transmount. Any help would be appreicated.

Thanks,

Mark

You want the through Hull transducer. Plastic is fine.

the humminbird rep should know, but it is the XTH 9 20

Thanks for the reply guys. I got hold of the company after about 20 minutes waiting but I have a new transducer coming. Once I got to talk to someone it went smoothly.