Wrapping a key fob in aluminum foil may reduce its exposure to relay theft. In these attacks, criminals use equipment to extend communication between a vehicle and its key, potentially allowing them to unlock and start the car without taking the fob. Foil can act as an electromagnetic barrier, but its effectiveness depends on complete coverage and an intact wrapping. Gaps, tears, or inconsistent shielding make it an unreliable substitute for a tested protective solution.
A purpose-built Faraday pouch offers a more practical option, provided it actually blocks your fob’s signals. Close it properly, then approach your vehicle and check whether keyless entry still works with the fob inside and no other key nearby. Test periodically because shielding can deteriorate. Keep spare keys protected too, and consider additional safeguards such as a steering-wheel lock. The goal is layered protection—not false confidence in a household trick that might fail unnoticed.