LandAirSea 54 GPS Tracker - Made in the USA from Domestic & Imported Parts. Long Battery, Magnetic, Waterproof, Global Tracking. Subscription Required

Why it's worth it

The LandAirSea 54 is a waterproof puck with a magnet strong enough to hold onto a frame rail. It's the one to buy when you want a tracker a thief will never find, and you're willing to crawl under the car to recharge it.

It's small enough and strong enough to stick where nobody looks. The whole device is a bit over two inches square and less than an inch thick, with the magnet built in. It'll hold onto the inside of a rear bumper, a frame rail behind a wheel well, or the underside of the engine cradle. No tools, no wiring, no visible plug. Someone would need to actually get under your car with a light to find it.

Weather doesn't bother it. It's waterproof, which is the whole reason under-chassis mounting works. Car washes, road spray, slush, a flooded intersection in July — none of that is what kills this tracker. Cheaper magnetic units tend to die the first winter they spend under a salted car.

From our review of 5 hidden car gps trackers, by Ben Carter, Tech Editor

What we like

• +It's small enough and strong enough to stick where nobody looks
• +Weather doesn't bother it
• +It updates fast enough to follow a moving car in real time
• +Motion-activated sleep buys back battery life

What to know

• –Somebody has to remember to charge it
• –The subscription costs more than the top pick's, and a lower rate requires a long prepay
• –The software is functional rather than pleasant