Interested in having your M4/AR AEG using 9mm magazines? The Mugen Fire Custom 9mm-Style Conversion Kit available at eHobby Asia should do the trick and you can use the 40-round mags for the Tokyo Marui UZI AEG as well... "Give your m4/ m16 that 9mm carbine look with this kit. Fits 9mm style mags into any Marui or Classic Army M16 mag well."