Ok so there have been many suggestions on this subject on several other threads, but there has also been much over ananlyzing. To keep cool in a suit you need heat transfer. Ok two ways to do this, conduction (your heat to another object) or convection (your heat to a liquid). These are done best at the Veinous points. Veinous points are where the veins and arteries are closest to the skin, allowing your heat from the blood to be transfered out. (also most usually used for getting a pulse from these arteries). These places are the groin, the neck, the wrists and brachial area (IE armpits). Any small device, no matter the 5*-10* difference in Temp APPLIED to these areas will have a significant difference on body temp. That apposed to needing a 15*-20* change in a shirt or other clothing item. A small pump, with reservior of cold water and the tubing running to thses places. I'll post back when I have the supply list.
"Look around the room. Get someone smarter than you and put them on the phone. Yes stupid, I can hold."
USMC CWO4 Sierra, OIF 09-1