I know this may be a silly question but . Do all modern-ish trucks have a 12 volt cigar lighter socket or a 24 volt ?
sometimes both
it should say on it. Whatever you do dont guess! Most sat nav’s are 12/24v. What wagon is it?
The reason I ask is to do with sat navs. Are all sat navs dual voltage?
The snooper S600 truckmate for instance.
Most sat navs and phone chargers will work on both mate
chippy:
I know this may be a silly question but . Do all modern-ish trucks have a 12 volt cigar lighter socket or a 24 volt ?
Most are 24V so assume they are. Check you charger to see if its does 12V & 24V, some have a sticker or markings on them.
Taken from the manufacturers page:
What’s included?
The following accessories are included free of charge.
Windscreen mounting bracket
12/24V In car charger
240V Home charger
USB cable
Snooper speed camera updater software
Quick Start Guide
PDF User Manual
Carry case
FM antenna for use with TMC
However,I can’t believe you bought it,and didn’t read the instructions. 
Ken.
Quinny:
didn’t read the instructions.Ken.
RTFM
Though theres always the old smoke test to see if it works
Hi . I haven’t bought it. Just needed to clarify that a 12 volt sat nav would work in a truck. So let me get this right my garmin i3 5 years old would work in a new artic?