Minelab coils are not necessarily interchangeable among different models of Minelabs. 705 coils will not work on other Minelabs like Etrac or Equinox. 705 coils only work on that series of detectors (705, 305 and 505). The Equinox is the most popular Minelab out there right now and would be a big upgrade from a 705 and not much more money than a 705. There will still be a big learning curve since the Minelab multi frequency machines sound and act differently than the 705 series machines. 705 series only change frequencies by changing coils whereas Minelab multi frequency detectors have the frequencies programmed into the controller and the coils have nothing to do with the frequency used.
