Hertz Car Rentals have some specific info on ther site - the Navman (brand name) unit they talk about is fully portable, can be transferred from vehicle to vehicle in just 20 seconds and as a brand are the best I have ever seen/used in a portable unit.
https://www.hertz.com.au/rentacar/by...=globNav_3_3_3
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Drive With Confidence With Hertz In-car Satellite Navigation
Whether you are travelling on business or on holiday, you can drive with confidence with Hertz in-car satellite navigation. No more fumbling with maps, searching for street signs and asking for directions.
You will never be lost or worried about finding your way to an unfamiliar destination with the remarkable NAVMAN in-car navigation unit as your guide. NAVMAN uses innovative street mapping software with the latest GPS technology to deliver a safe, easy to use and dependable details into the navigation unit, and the NAVMAN responds with voice and visual instructions for a stress-free journey.
NAVMAN Features- Colour display
- Clear accurate visuals
- 3D Map
- Current position display
- Back to track automated re-routing
- Navigate to your destination
- Navigate to multiple destination points
Hertz offers this superior technology at major airports and selected downtown locations throughout Australia, for a nominal daily charge.
The NAVMAN unit is available in our Fullsize Economy vehicles (Ford Falcon or similar). "