Значит, нужно полагать, очки укомплектованы парой сменных линз типа 3 и 4, предпогалающих баллистическую защиту с покрытием против царапин.Lens Types with the Sun, Wind and Dust Goggles (SWDG)
The lenses are classified by type:
* Type 1 and 2 (thin acetate) lenses are no longer used since they offer no ballistic protection.
* Type 3 (clear) and type 4 (sunglass) lenses are a single piece, simple curve, injection molded polycarbonate design with an abrasion resistant coating.
* Type 5 and Type 6 lenses offer laser protection.
The lenses of classes 3 through 6, with a nominal thickness of 2 mm, provides ballistic protection.
Вообще источник указывает такие маркировки:Числовой код, идущий первым, — это NSN (National Stock Number).8465-01-328-8268 SWDG kit with Type 3 and 4 lenses. Includes case and frame with strap
8465-01-439-3506 Type 5 green lens, 2WL laser protection (lens only)
8465-01-439-3511 Type 6 brown lens, 3WL laser protection (lens only)
8465-01-109-3997 Type 3 clear lens (lens only)
8465-01-109-3996 Type 4 gray lens (lens only)
В качестве иллюстрации (изменено):
Источник: http://www.olive-drab.com/od_soldier...ewear_swdg.php