The P-Mag Coupler from California Competition Works is a part designed specifically for competition use. It works with Magpul P-Mags, coupling either two 30-round mags or one 20-round mag and 30-round mag into a single 60 or 50-round mag, respectively. CCW also offers a variant for .308 Magpul mags which turns two 20-round mags into a single 41-round mag.
