There was a rule that came out this summer that applied to heavier
aircraft, I believe turbo-props, but don't quote me on that. Be sure to
check the very latest version of the FARs. If you google 406 ELTs like
I did you might find it.

BTW, if you can wait, I know Pointer (and likely some of the other
companies) is coming out with a better 406 ELT in 2005. Currently Artex
has the only US 406 ELT and it's like 1.5K and does not include a GPS
encoder. The Pointer one is suposed to retail at only 1K and include a
built in GPS.

Helen