These option parts are produced for Bandai's 30 Minute Missions line of model kits, but they work for 1/144 Gundam models as well. The rifle's Gatling-type barrel option doesn't really fit the look of the rest of the gun, but the other barrel options work well. The plastic feels somewhat soft, and can be cut a little too easily, but still take well to plastic cement, plastic putty, and some light sanding to remove nubs and even out surfaces.