DETAILS Brand: U.S. Military Surplus Caliber: Designed for .50 Caliber Browning Machine Gun (BMG) rounds, though often stenciled for other types like 5.56mm or 9mm. Opening Mechanism: Hinged, fully removable lid. Closure Type: Side-mounted, heavy-duty clamp-down latch (compression bail latch). Capacity: Approximately 4.25 Liters; can hold up to 34 lbs of gear or roughly 1,200 rounds of loose .223/5.56 ammo. Locking: Includes a standard latch; some surplus units are sold with after-market locking hardware kits installed. Proofs: Airtight and watertight via a rubber O-ring gasket seal.