Nat, the transducer is just a paddle wheel with magnets on each spoke and a coil They are all the same inside and just need to be rewired to the new unit. Airmar (www.airmar.com) is the OEM for Standard Horizon and Ramarine for sure and probably for most of the other manufacturers too. As a result, they all fit the same hole. I do not knwo about the tac tic wireless but it is likely also the same. Call them. They are pretty helpful.

Larry

:: Hi -
::
:: I need to replace the knotmeter on Elise - do you have
:: any recommendation for a good instrument set. I don't
:: know if there is a standard throughhull diameter, but
:: would love not to have to drill holes into the hull...If
:: it could be just drop and replace, it would be fabulous.
::
:: Any pointers appreciated!
::
:: Thanks!

:: Nat