There's a slight catch!

Credit: maccosmetics/Instagram

Need a new nude? Ran your crimson red bullet totally dry? MAC is giving you the chance to restock an item in your lipstick collection for free. For the next 10 days, MAC is offering a promotion that you’re going to want to jump on, stat, and here's how it all works.

The brand's #MACLipsLipsLips sale gives you the chance to score a free tube of lipstick when you buy any two lip products from the MAC stores or online. The whole idea is that the new trio allows you to easily test out a new trend, whether you're going for something glittery, glossy, matte, or metallic.

MAC has even launched a feature on the brand website that shows you pics of a few different trends, and then shops out the exact three products you'd need to recreate the look for yourself, along with a tutorial on how to apply each.

But there's another slight catch. You can't get any MAC lipstick for free—you can only pick from a selection of six different shades, and they include a pale pink, a rose plum, a fuchsia, a deep royal purple, a pastel purple, and a bright red shade.

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Still not too shabby, right? The offer officially ends on the 25th, so you'll want to head over to or into a store now.