When referring to Combat Operations, What is the best piece of equipment(military/civilian) that helped you through deployment?

I know many have deployed and there are alot of "gear junkies" out there, but what is the one thing, or multiple things that you believe helped you through deployment? For me, here are a few things:<div><div><br></div><div>1: The Combat Action Tourniquet, by far one of the proven life saving devices as we found out that bleeding of the extremities was the number one source of battle deaths.</div><div><br></div><div>2: The Garmin Foretrex 401, simply put it takes all the abilities and features of your Old School PLGR and Newer DAGR and puts it right on your wrist. This came extremely in handy for me while on Dismounted Patrols in the dangerous region of Wardak, Afghanistan. 10 digit grid immediately! Plotting your Waypoints and Areas of Interests have never been easier.</div><div><br></div><div>3: The CROWS System, no need to put the gunner in harms way anymore. Extremely accurate and not to mention better vision at night(Thermal) yes many may not like it and say "Owh well a real human can make a better split second decision" but in reality, its a great design and keeps our gunners safe from sniper fire and/or Grenades being dropped in the hatch from overpasses and such.</div></div><div><br></div><div>Of course a number one thing that also helped me through deployment is internet, if we had it...</div>