From the information I have required, The Navman fuel unit connectas to either the fishfinder or there Gps units (although not all of them).
Connection is made via a cable link that plugs into the back of the fishfinder or Gps. If you go to WWW.plastimo.com
you will find out more details on this web site. I managed to download an instruction manual from the web, very good reading.
I spoke with Daniel on the subject of the fuel unit with fishfinder and he is very happy with performance/accuracy. As always there were some people who mentioned reliability could be an issue with time.
As Charles has already stated, instalation seems to be very easy, however, manual does state that you need to calibrate fuel unit first (25lts) to gain better accuracy.
One thought I did have last night, if we were able to purchase unit through Charles. Should there be any warrenty/service issues would we have to return unit to retailer in Jersey? Charles any thoughts.
My decision to buy has been made on the functionality of the unit combined with a Gps system, recomendations made on Ribnet and of course the price.
Cheap is not always chearfull