IS4537-2303 ISP CaseOVERVIEW Shifting loose cargo can slow down your operations and put the mission at risk due to damaged freight. The new ISP Case from Pelican virtually eliminates cargo movement with its unique Inter Stacking Pattern (ISP). This patent pending system is compatible with six different case sizes, ranging from 4 to 25 cubic feet of storage. Equipped with a silicone sponge O ring and pressure release valves, the ISP Case is impervious to extreme weather