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Travel is stressful enough without getting pulled aside by security for forgetting about the shampoo in your carry-on. To avoid having to toss entire bottles of perfectly good toiletries into the trash outside security, get familiar with the TSA liquids rule.

The TSA liquids rule — also known as the 3-1-1 rule — is actually quite simple: All carry-on liquids must be in containers that are 3.4 ounces (100 milliliters) or smaller, and these containers must all fit into a single quart-sized, resealable bag. Note that each container itself must be no larger than 3.4 ounces, or it will need to go into your checked luggage — regardless of how much liquid is actually inside.

Does toothpaste count? The TSA treats all aerosols, gels, creams and pastes as liquids. That means that things like toothpaste, hairspray, shave gel, lip gloss and even peanut butter are all subject to the 3-1-1 rule.

Is the TSA liquids rule different for international flights? Basically, no; if you’re flying to or from the United States, your carry-on luggage must follow the 3-1-1 rule. The only exception is for items purchased at airport duty-free shops within 48 hours of your flight (with a receipt to prove it). These must also be packed in a transparent, secure, tamper-evident bag by the retailer. If not, they’ll need to go into your checked baggage after you land and clear customs, before continuing on any connecting flights within the US.

What about medications? Medications, breast milk and baby formula/food are exempt from the 3-1-1 rule — just be sure to bring proper medical documentation. These items don’t need to be in a zip-lock bag either, but should still be clearly labeled, declared, and ready to be screened separately from the rest of your belongings. Per TSA procedures, you’re also allowed “ice packs, freezer packs, gel packs, and other accessories … in a frozen or partially-frozen state to keep medically necessary items cool.” Again, these should be clearly labeled, as they’ll still need to go through the screening process.

Now that you know the rules, shop the top-rated flight-friendly packing products on Amazon to make your next trip through the security line easier than ever. (And because portable chargers can be just as confusing as liquids when it comes to figuring out what’s allowed onboard, we’ve also created a whole guide about TSA-friendly battery packs here.)

TravelSnugs LiquiSnugs leakproof silicone travel bottles, set of 3 ($12.95;

It’s time to stop wasting money on mini toiletries you don’t even really like. Instead, transfer your favorite products to reusable travel bottles like these from TravelSnugs. The LiquiSnugs feature built-in suction cups, so you can stick them onto a shower wall, and the soft silicone exterior makes it easy to squeeze out every last drop of shampoo or soap. They also have built-in product labels that you can change just by twisting the cap, ensuring you’ll never accidentally squirt body lotion all over your hair again. Best of all: LiquiSnugs are guaranteed to be 100% leakproof or you’re entitled to a refund.

Cable in the Bay TSA-approved clear toiletry bag ($8.99;

Reusable toiletry containers are more durable, and ultimately more economical, choices for carry-on liquids than flimsy zip-lock bags. Cable in the Bay’s TSA-friendly case features a zipper top and is made from waterproof PVC, earning it 4.6 stars from more than 1,000 reviews.

Lermende TSA-approved clear toiletry bag, set of 3 ($12.99;

This highly rated, flight-friendly liquids bag is also made from waterproof PVC. Lermende’s version comes in 16 colors, and you can also choose a set with attached handles for carting to and from the bathroom when you reach your destination. Note that while this set comes with three cases, you’re only allowed one liquid bag per traveler when flying.

Peak Gear silicone cream jars, 3 pack ($10.29;

Put face creams, gels, petroleum jelly or any other thick liquid in these highly rated jars from Peak Gear. The jars are made from food-grade plastic and silicone and feature wide mouths that make them easy to fill and clean. They’re also guaranteed to be leakproof and backed by a lifetime warranty, so you can fly with them for years to come.

Ethique solid shampoo bar ($16;

Solid toiletries are a great choice if you’re running out of space in your liquids bag, and they also happen to be much more eco-friendly than their plastic-packaged counterparts. Ethique is a popular option for good reason: its products are soap-free, vegan and compostable. The company also sells highly rated solid conditioners ($18; and dual shampoo/shave bars ($16;

Vonpri soap box holder, set of 2 ($7.98;

Because you’ll definitely need something to pack your new solid toiletries in, this set of two soap holders comes with a free mesh “soap saver” bag meant to create more suds and help your bar last longer.

Bago hanging toiletry bag ($25;

Bago’s hanging bag is perfect for your non-liquid toiletries (or for transferring all your toiletries into once you land). In addition to its handy top hook, the spacious bag features tons of internal space and waterproof, ripstop fabric.

Lewis N. Clark RFID-blocking neck wallet, travel pouch, and passport holder (starting at $13.74;

Keep your phone, passport and credit and debit cards all in one safe place with this RFID-blocking wallet/travel pouch from Lewis N. Clark. The pouch is small enough to toss around your neck, but roomy enough to also hold extra cash and small items like lip balm or earbuds — so you don’t have to worry about misplacing anything in the rush of going through security.

Shacke Pak packing cubes, set of 4 ($24.99;

Packing cubes are hugely helpful in keeping your luggage organized, no matter how much stuff you’ve crammed in, and make it easier to grab what you need when you need it (for example: your liquids bag when going through security). This set from Shacke Pak comes with four cubes in various sizes, plus a lightweight sack for dirty laundry. It has 4.8 stars from more than 8,000 reviews.

Note: The prices above reflect the retailer’s listed prices at the time of publication.