Yep I guess we got the new ones from 2006 in 2008 and that’s the batteries I’m thinking about. Used the one y’all are looking at in 2005
Wikipedia - In November 2006, three new versions of the AN/PAS-13 were ordered by the U.S. military. The Thermal Weapon Sights II include three new versions, a Light, Medium, and Heavy. All three models weigh less than the originals, weighing 1.8 lbs, 2.8 lbs, and 3.9 lbs respectively. This reduction in weight and size is due to improvements in the sensors, as well as the ability to now run the sights without being cooled. The Medium and Heavy models maintain zooms of 5× and 10×, while the Light model has a zoom of 1.55× and a FOV of 15 degrees. All three models now run on lithium AA batteries, with the Light having a battery life of 5 hours, the Medium 6.5, and the Heavy 6.5.
[3] The US Armed Forces designates version 2 as MTWS (Medium Thermal Weapon Sight), and version 3 as HTWS (Heavy Thermal Weapon Sight).
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