Hi

If this is too basic then apologies but the OS is the operating system, a bit like windows XP is to your pc. The navigation cd's are the actual maps that run on it.

Depends on your exact car date, but your operating system is around 2 years old and there have been later releases that have improvements like 3D map pespective. You can work out which version from the number displayed in the top corner of the 'set' screen 4-1/91 would be the latest. Post that number and it can be identified easily or search the board

Maps themselves. It really down to you. Have many roads changed in your area. If not then perhaps of limited value.

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X5 3.0i Sport - Brembo rotors, Hamann Exhaust, custom Xenon & AE lighting, Retrofit Bluetooth
Z4 3.0i Roadster
CJ10a Jeep
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