These are the original CASE-GARD ammo boxes. Made of virtually indestructible polypropylene that will not warp, crack, chip, peel, expand or contract, MTM CASE-GARD rifle ammunition cases are still the first choice of rifle enthusiasts throughout the world. MTM's famous living hinge boxes are guaranteed for 1 million open-close cycles or ten years. Snap-Lock latch protects contents from accidental spilling. In the late 1960's, the RS-S-50 was designed specifically for benchrest shooters. The CASE-GARD 50, which is available in eight sizes will hold .22 Hornet to 375 Remington Ultra Mag., with each cartridge resting in its own individual compartment. Each CASE-GARD 50 ammo box is supplied with a load label for recording load and sight data. All rounds listed as bullet up, unless noted. See ammo box charts for more calibers. RS-50 for cartridge sizes: 17 Fireball,17 / 221 / 223 Rem., 223 Rem. HP,17 MACH 4, 204 Ruger, 222 Rem. Mag., 300 Sherwood, 300 Whisper, 32 Ideal, 32 Win. S.L., 6mm-223 Rem., 6 x 47. Max. OAL= 2.49"