MBX Extreme

AR-15 Modular Extension Basepad for Gen 3 PMAG

$39

The basepad for the PMAG above: four more rounds in a 30, and the dovetail that lets two mags lock together with no tools.

MBX's aluminum extension basepad for the Gen 3 PMAG. It adds 3 rounds to a 20, 4 to a 30 and 5 to a 40, and it carries MBX's patented Inter-Loc dovetails, so two mags can be coupled with the Inter-Loc block, or a single mag fitted with the stabilizer wings for a monopod, in seconds and without a tool. MBX is blunt about the one step that matters: the factory plastic clip on the PMAG spring has to come off before the basepad goes on, or you get neither the function nor the extra rounds. Sold one basepad at a time; the block and the wings are separate, or come together in the Coupling Set and the Complete Inter-Loc Set. The picture shows the whole system built up, two red basepads on the blue block with the blue wings. Retailers list it in black, blue and red. Made in Loudon, Tennessee. Shooters Connection carries it at $39; MBX's own store sells it direct.