LL Bean Synthetic Base Layer — Men's Lightweight, Black Coffee Leaf Camo (a fairly brown color with a strange pattern). I'm also selling a (mismatched) top here

I can't find the listing on the LLB site for this exact color, but the general specs are here.

From the product page:

Designed for adventure—our lightest weight base layer pants are packed with performance properties for all-day comfort.

  • Standard Fit: Sits lower on the waist and straight through the hip and thigh for a streamlined look.
  • Fitted through hip and thigh.

When it comes to base layers, we know how hard it can be to find the perfect pick. That's why we designed our L.L.Bean Base Layers to take the guesswork out of finding the right weight, or fabric, or fit. These lightweight pants are perfect for transitional weather activities, like hiking or camping, and it actively wicks away moisture so you stay dry and comfortable when the weather warms up. They're even great under waders while fishing.

Again, I'm also selling a mismatched top here: https://www.ebay.com/itm/276411183487