Just a heads up... I have several of the Red, White and Blue T-Loc SYS 4 Coolers with the liners removed, that I use for tool storage. Some, but not all of them, have a small through hole in the center of the systainer bottom. It appears to be about 0.1 mm in diameter. I'm guessing that they were drilled to drain any condensation that forms in the void between the cooler liner and the systainer wall.
But, I'm not using them as coolers. So, I plugged them with silicone to seal them.