All Berry’s Ammo Boxes are made from high impact polypropylene for increased strength against cracking, chipping, warping, expansion, or contraction. Their Model #407 50 round boxes feature a stronger, flip-top design, allowing the securing of ammo storage with easy one-handed operation. Along with a translucent lid, they now come with a black base for increased strength and a clean look. They are stackable, they carry a lifetime warranty, and they are made in the USA.