This is the MDT Mag Loader for AICS magazines, a dedicated thumb assist loader for AICS short action mags.
The large surface area and spring actuated loader allows you to push down a round and load another on top with a fraction of the finger pressure used for manual loading.
Great for cold fingers or shooters with arthritis it's a welcome addition to the winter range bag.
Tested and proven with .223 and .308 family cartridges.