The Right Magnets for Your Wireless Tow Light | TowBrite
When you're shopping for a wireless tow light, the magnet strength almost always comes up as a decision point. Most TowBrite light bars are available with either 100lb or 200lb magnets, and the natural assumption is that more pull is always better. In practice, the right answer depends on how you mount the bar, what kind of vehicles you tow, and how often you're moving the light from one job to the next.
For the vast majority of operators, 100lb magnets are more than enough. A standard light bar sitting flat on the roof or deck lid of a sedan or pickup is being held down by gravity as well as the magnets, and 100lbs of pull per magnet is far more force than the bar needs to stay put at highway speeds. The light comes off easily at the end of the tow, doesn't fight you when you reposition it on the next call, and is a lot kinder to clear coat. If you tow cars and light trucks day in and day out, this is the size to reach for.
Where 200lb magnets earn their keep is in horizontal mounting situations, where the bar is stuck to a vertical surface and hangs out sideways from it. Think of the back of a box truck, the rear door of a van, or the vertical face of a piece of equipment — anywhere the magnets are pulling perpendicular to gravity instead of with it. In those cases the extra holding power gives you real peace of mind, especially over rough roads or long highway pulls. Operators who routinely tow oddball loads, equipment, or anything where the bar needs to grip a vertical panel will appreciate the upgrade.
The trade-off is worth being honest about. 200lb magnets are genuinely hard to remove, and that strength is what causes problems on painted vehicles. It's very easy to slide the bar sideways across a roof or trunk lid when you're trying to break it loose, and that sliding motion is exactly what puts hairline scratches into the clear coat. Even with a clean magnet and a clean panel, a 200lb pull concentrates a lot of force on whatever dust or grit happens to be between the magnet and the paint. If most of your work is on customer vehicles where appearance matters, the heavier magnets can quietly create more callbacks than they prevent.
It's also worth remembering that magnets only work on steel. Plenty of vehicles on the road today — fiberglass-bodied trailers, aluminum-bodied trucks, Corvettes, certain panel vans, and a growing number of EVs with composite body panels — give your magnets nothing to grab. For those vehicles you'll want a suction cup mounting kit, which TowBrite offers as an accessory that swaps right in for the magnetic feet. A good set of suction cups will hold a light bar securely on any smooth, non-porous surface, and it's the only safe option when steel isn't on the menu. Most operators end up keeping a set in the truck regardless of which magnets they ordered the bar with.
One last trick from the old-timers, and it works no matter which magnets you're running. Clip a dog leash to the handle of your tow light, lay the leash across the trunk opening, and close the trunk on the loop end. It takes about five seconds and costs you nothing, but if the bar ever does come loose — a strong gust on the highway, a bump that catches the magnets just right, or a vertical mount that finally gave up — the leash keeps the light tethered to the vehicle instead of bouncing down the road behind you. It's saved a lot of operators from chasing a $700 light bar through traffic, and it's a habit worth building regardless of whether you went with 100lb or 200lb magnets.
If you're trying to make the call, the simple rule of thumb is this: pick 100lb magnets if you primarily tow cars and light trucks on horizontal surfaces, step up to 200lb if you regularly mount on vertical or heavily-vibrated surfaces and accept the higher scratch risk, and add a suction cup kit either way so you're never caught out by a fiberglass body or an aluminum panel. And no matter which way you go, throw a dog leash in the toolbox.