'Fountain of youth': This anti-aging serum has been a best-seller for over a decade—and it's on sale right now!

Searching for the perfect anti-aging serum can be exhausting. With so many formulas promising to get rid of fine lines, wrinkles and dullness, which one do you pick? There’s also the price to consider. Serums are notoriously expensive (after all, they’re making us look younger).

But there’s one serum that’s been a favorite since it launched in 2006. It checks all the boxes — it fights wrinkles and brightens skin — and doesn’t cost a small fortune: Philosophy When Hope is Not Enough Facial Firming Serum.

Walmart customers swear by this powerful anti-aging potion.

“I’m 65 years old, and I'm told I look 50!” raved one customer. It really makes my skin look firmer and glowing!”

One loyalist called it “Fountain of youth,” and added, “This product is incredible! It feels so good on your face, and I feel younger. You definitely get what you pay for —plus reverse aging, in my opinion. I've been using this product for over ten years!”

So what makes this anti-aging serum so great?

For starters, it’s packed with antioxidants and peptides to brighten skin, reduce signs of aging and protect against future damage. The lightweight serum is oil-free and also made with hyaluronic acid, which hydrates and plumps skin.

At the end of the day, the simple, straightforward formula does what you need it to do: Fight those signs of aging —fine lines and wrinkles — while boosting firmness. All you need to do is apply a few drops on your face and neck morning and night, and watch fine lines smooth out and dull skin transform into a radiant, youthful complexion.

“This is the best firming facial serum!” proclaimed one fan. “I love how it absorbs into my skin and smooths out my facial wrinkles. I have rosacea, and this serum seems to even out my skin tone. This is my favorite.”

“I have tried many serums, expensive as well as drug store brands, and this one is by far the best yet! It is very light on the skin, never sticky or greasy and absorbs quickly. It balances my skin perfectly and gives me such a healthy glow that I hadn't seen in a while,” explained another customer. “It improves the texture of my skin also as well as helping with some slight wrinkles. Another wonderful Philosophy product that has become a staple in my routine.”

Shop it: Philosophy When Hope is Not Enough Facial Firming Serum, $40 (was $45), walmart.com

The editors at Yahoo Lifestyle are committed to finding you the best products at the best prices. At times, we may receive a share from purchases made via links on this page.

The reviews quoted above reflect the most recent versions at the time of publication.

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