A different take on modern speed loaders. The ATW speed loader was intended to work with any AR magazines not limiting you to standard 30 rounders liker other brands. Ours have been tested with 10, 20, 30, and 40 round magazines from MDT, Magpul Gen2s and Gen3s, and classic U.S.G.I Metal mags. This model is also collapsible for easy storage in your range bag. In short, if it goes in your AR magwell it will work.
 
This model was intended to be used with .223 Rem, 5.56 NATO, and .300 Blackout. Other calibers can theoretically work as long as they use the same parent casing to 5.56, and are close to the same length.