A company called CROSS Industries makes 10 round AR-15 magazines with a specially designed floorplate that allows to couple the magazines by attaching the floorplates together. The result is an assembly consisting of two 10 round magazines attached together upside down with overall dimensions similar to a standard 30-round magazine.

The floorplates of these magazines are bidirectional and angled. That allows to couple the magazines in four different configurations of the lower magazine orientation and overall angle of the assembly. By changing the floorplate and lower magazine attachment directions you can have:

• Straight assembly body with lower magazine facing forward (bullets forward)
• Straight assembly body with lower magazine facing rearward
• Curved assembly body with lower magazine facing forward
• Curved assembly body with lower magazine facing rearward

The CROSS Industries magazines are made of transparent polymer. The company claims that their material is superior to what is used in competitors’ magazines. Here is how they describe the material properties:

Designed to perform in the frigid north, our polymer is a new to market material that is specially formulated for cold weather impact resistance. Its unique properties allow virtually no change in mechanical properties from 73f/20c to -22f/-30c, whereas most polymer materials used for magazines have between .125-.25 the strength at -22f/-30c compared to room temperature. This gives us on average 3-8x better impact resistance than competitive materials at -22f/-30c.

The company doesn’t clearly specify on their website at what applications this coupling solution can be most beneficial. I think that most likely, the main market for this product will be the states and countries that have a 10 round magazine capacity restriction. By having such coupled 10 round magazines, you should still comply with the legislation but have an arguably quicker reloading possibility and overall magazine shape similar to the 30-rounder fitting the standard pouches. Now, keep in mind that these are just my assumptions and you need to make sure you are not breaking your local laws.
The obvious disadvantage is, of course, the lower magazine being exposed to elements.

There is no pricing and availability information yet. As soon as it appears, I’ll update the article.