The GEN-II Pro Series is an evolution of the Mfour model, the PRO rifle adds an 11.8" free float aluminum for end with 8-position Quad Picatinny rail. All other characteristics remain unvaried: 16" heavy match, parkerized barrel, steel bolt, MIL-SPEC components, 6-Position Adjustable Stock, and ships with (2) 28+1 round magazines.