We love our landairsea 54 gps tracker, it really helps me sleep better at night knowing where our camper/travel trailer is at. We used to keep it in a storage facility, and I read so many stories where people still had their trailers stolen and the facilities were no help. I researched better ways to prevent someone from taking our trailer, and those solutions got expensive and they were not guaranteed to work. I eventually came to the conclusion that it will be impossible to 100% prevent someone from taking out trailer, but if I could track where it went, I had a great chance of getting it back. I still use prevention security on the trailer, but now if I wake up one morning to an empty driveway, I know I can track it back down. The landairsea 54 allows direct 12v hookup, so it draws power from our camper batteries, that gives us a very long run time. Even if they disconnect our batteries, the landairsea 54 has an internal battery to keep tracking. We prepaid the subscription, so the monthly cost was far less than what we paid the storage facility. On top of that, we can run reports to track the mileage the trailer has gone that year, so we know what to maintenance. We love our device and would buy it again.