yup can confirm they can use a dampening field. it just plug directly into the cig lighter. i had one for my Van (as it had a tracker) just switch it on then plug it into the lighter to charge it up. so trackers are useless, unless u get the SMS ones that txt u when the GPS signal is not achieved. they are bucks tho.
dont see the point myself. also if THEY have one of those devices i doubt you would ever see it again.