While traveling solo can be very rewarding, it can also feel a little scary. If you’re looking for a way to have added security and peace of mind on your trips, one flight attendant may have found the solution with door stop alarms.

TikTok user @flywithmerm often shares with her 181,00 followers the tips and tricks she’s learned from traveling the world with her job. Recently she called these portable safety devices one of her “travel must-haves” because these clever gadgets give you an extra layer of protection anywhere you go.

They may look like your average door stopper, but the safety device will actually set off an alarm when triggered, quickly alerting you if someone is tampering with your door. “If you stay in hotels a lot, or AirBnB’s a lot, this is perfect,” she said. “You place it underneath your door, but it’s very sensitive. It has three levels of volume, and trust me this will wake up the deepest sleeper if anyone tries to get in your room,” said @flywithmerm in her video.

After sharing the security door stoppers, the TikTok video quickly went viral, racking up more than 5.2 million views and 405,000 likes from users who became interested in getting one for themselves. “I need one,” wrote one commenter. “Add to wishlist,” said another.

Courtesy of Amazon

To buy: amazon.com, $9

While @flywithmerm didn’t specify exactly which option she uses herself, she did note that she bought it on Amazon, which luckily has a large selection to choose from. Even better, they are all actually affordable. You can get a singular alarm for as little as $9 or a four-pack for only $19. Shoppers love how easy they are to use, and there’s no setup involved. You just need to pop in a battery and then place the stopper under your door.

Most Amazon reviewers say they use the door stoppers when they travel, but others say they like to use them at home too. A few even report that the alarms work great for children or sleepwalkers, since they will alert their loved ones that they may have wandered off.

Looking to give one a try in your home or on your next trip? We rounded up five of the most popular options on Amazon. Shop the under-$10 single door stop alarm above, or keep scrolling for additional models and multipacks.

Courtesy of Amazon

To buy: amazon.com, $17 for 3 (originally $18)

Courtesy of Amazon

To buy: amazon.com, $19 for 4

Courtesy of Amazon

To buy: amazon.com, $14 for 2 (originally $18)

Courtesy of Amazon

To buy: amazon.com, $14 (originally $15)

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