Reference Manual 43 - National Park Service

Vest. The vest is worn as part of the layering system. When worn as outerwear with the Field Uniform, the badge and name bar will be attached. Turtlenecks. Turtlenecks are always worn under a long-sleeve shirt. The neck portion must be folded over one time. Turtlenecks should be free of fading and pilling. ................
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