They’re not technically free, but Amazon Prime’s sample boxes come pretty close!

The online giant sells a number of sample boxes exclusively to Prime members that are filled with things like beauty supplies, coffee and tea, dog treats and more.

Here’s how it works: You buy a sample box, then Amazon gives you an equal credit for a future purchase.

RELATED: Is Amazon Prime worth it for you? Take this quiz to find out!

Get more out of your Amazon Prime membership with this exclusive perk

For example, the Skin Care and Hair Care Sample Box costs $9.99 and comes with at least 10 samples. I ordered one and got the following items:

• Aquaphor Advanced Therapy Ointment Body Spray
• Simple Cleansing Facial Wipes
• Carol’s Daughter Black Vanilla Shampoo & Conditioner
• Crest 3D White Professional Effects Whitestrips
• Le Petit Marseillais Extra Gentle Shower Cream
• Oral-B Glide Pro-Health Deep Clean Cool Mint Flavor Floss
• Acure Organics Coconut and Argan Oil Cleansing Towelettes
• Nivea Oil Infused Lotion Vanilla and Almond Oil
• Roc Multi Correxion 5 In 1 Anti-Aging Cream with SPF 30
• GLISS Hair Repair Shampoo
• GLISS Hair Repair Conditioner
• Aveeno Skin Relief Gentle Scent Lotion For Extra Dry Skin
• Aveeno Skin Relief Gentle Scent Body Wash

You’ll find instructions to redeem your Amazon credit inside the sample box. You can use your credit by visiting amazon.com/sample-boxes, but it’s only good on select items in a particular product category.

I was able to choose from 370 beauty and personal care items, including regular sizes of the samples.

There are a few things I noticed while browsing the selection: Many of the qualifying products are more expensive than the credit amount, some of them are add-on items and others are only available with Prime Pantry.

If you don’t want to owe anything, sort items by price. I found something for $9.99 — the exact amount of the credit.

Not interested in beauty and personal care samples? Here are some of the other boxes that Amazon offers, which typically take a week or two to ship:

• Household sample box for $9.99 with $9.99 credit
• Women’s daily beauty sample box for $7.99 with $7.99 credit
• Coffee & tea sample box for $9.99 with $9.99 credit
• Mr. Olympia sports nutrition sample box for $9.99 with $9.99 credit
• Men’s luxury grooming box for $19.99 with $19.99 credit
• Men’s grooming sample box for $9.99 with $9.99 credit
• K-Cups coffee sample box for $7.99 with $7.99 credit
• Luxury sun care sample box for $14.99 with $14.99 credit
• Aveeno sample box for $7.99 with $7.99 credit
• Purina cat food sample box for $6.99 with $6.99 credit
• Dog food and treats sample box for $11.99 with $11.99 credit

“Amazon sample boxes are a great way to try products without a huge commitment, then with the future credit you can get your money back, making the initial box free,” said Charis Brown of ClarkDeals.com.

Before you buy a sample box, follow Clark’s #1 Amazon rule and read the reviews! Some boxes are better than others.

If you’ve purchased an Amazon Prime sample box, was it worth it? Tell us what you think on Facebook, Twitter or right below in the comments!

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