The R-100 come in two sizes that will cover the vast majority of all modern ammunition. Bullets can be stored up or down for most calibers. Made from virtually indestructible polypropylene and comes with MTM,s 10 Year Guarantee on living hinge products. This textured box comes with a handle for easy transporting. We highly recommend that you use the 100 round chart to be able to know which box would be best.