The Wosport MK4 Chest Rig MP7 Magazine Insert is a quick and easy way to convert any existing kangaroo flap or chest rig pocket into an SMG ready loadout. With hook and loop velcro, this magazine insert can easily attach onto many popular plate carriers and kangaroo pockets on placards or chest rigs. The MK4 Chest Rig MP7 Magazine Insert can fit up to 4 MP7 style magazines. However, this insert can still hold a plethora of larger sized SMG style magazines such as UMP, Scorpion Evo, X9, and PP19 style magazines. This insert will not fit P90 magazines.