The United States has agreed to sell Pakistan over 1,200 thermal sights ($17 million worth). These are apparently the AN/PAS-13 “thermals”. This device enables infantry to see through darkness, mist and dust storms because it can make out differences in heat. Over 100,000 of these sights have already been delivered are on order mostly for U.S. troops. But close allies of the U.S., like Canada, Britain, Australia and the like, have also ordered these rifle and machine-gun accessories. European firms have also developed similar systems.
Troops operating in Iraq and Afghanistan have found these lightweight thermal sights invaluable. Since first appearing in 1998, for use by Special Forces troops, the AN/PAS-13 has gone through several upgrades. The latest version is the AN/PAS-13E. It is a little heavier than earlier models, but has longer range and more reliability. The 2006 redesign was a major improvement in reliability and sturdiness, which made thermal sights much more useful, and popular, among combat troops.
The current AN/PAS-13E actually comes in three sizes, to accommodate the different ranges of infantry weapons. The smallest one (LWTS), weighing .9 kg/1.95 pounds, is used on your basic M-16 or M-4 assault rifle. This sight has a range of 800 meters (for detecting individuals) and 3,100 meters (for detecting vehicles) and 4.8x zoom. It uses 4 rechargeable lithium batteries which gets you about 7-12 hours of use per charge. Resolution is 320x240 pixels. There is a new version of this model (AN/PAS-13G) that is lighter and more reliable and meant for use on assault rifles. The G version costs about 20 percent more and there is a commercial version that lacks some of the military capabilities. These may be the ones Pakistan is getting.
The next version (MWTS) weighs 1.2 kg/2.5 pounds, has a range of 1,400 and 4,800 meters and is used in 5.56mm and 7.62mm machine-guns.. The heaviest version (HWTS) weighs 1.5 kg/3.3 pounds, has a range of 2,300 and 7,300 meters, and is used by heavy machine-guns and snipers. This one also requires six AA batteries (for 6.5 hours). Both the heavier models have 3x zoom and 640x480 resolution for the user. All models can be used on rifles but because of weight considerations the heavier sights tend to be used on larger weapons with longer range.
Large quantities of the AN/PAS-13 began showing up in Iraq and Afghanistan in 2007 and since everyone wants one. Over 90,000 have been delivered so far. The U.S. Army plans to buy as many as 100,000 AN/PAS-13 sights (at a cost of over $10,000 each).