Down Imaging from hummingbird...
 

Here it is. A shoot thru hull down imaging transducer from humminbird. Humminbird has a tx exchange program. If you buy a di unit, you can swap the stock unit with the shoot thru model for free by sending it in.

http://fishfinders.factoryoutletstor...ih-9-di-t.html

Matches up to the new 596di and 570di units.

Sweet. 4000 watts, color and down imaging for less than 500 street.

http://www.anchorexpress.com/Product...tCode=408110-1

The 570di is a black and white, down imaging unit for less than 300.

Yey. Maybe on my next kayak.

Check out some user pics I found on the net.

http://i137.photobucket.com/albums/q...bay/S00282.jpg

http://i137.photobucket.com/albums/q...bay/S00187.jpg

http://i137.photobucket.com/albums/q...bay/S00158.jpg

http://i137.photobucket.com/albums/q...bay/S00140.jpg

http://i137.photobucket.com/albums/q...g?t=1264263410

http://i137.photobucket.com/albums/q...r-03-25-10.png

http://i137.photobucket.com/albums/q...rgepinhall.jpg