"An Underquilt protector is a secondary layer of lightweight fabric that hangs below the underquilt and/or hammock bottom. It’s useful in cooler weather to give extra wind and weather protection to your hammock bottom, and allows for the use of a smaller tarp than would otherwise be needed.  
 
It can be attached to any of the XLC hammock configurations (no top, net top, winter top).  It can also be zipped directly to the XLC Topcover to create a full-on winter sock (The Chinook) that puts you, your hammock, and all your insulation inside it’s own wind and water resistant breathable microclimate. 
 
*NOTE: The underquilt protector can only be zipped to the new style XLC zipper configuration purchased after October 2017. You can still use the UQP with the old style XLC by tying it on with the black ribbons using shoestring knots."
 
The above wording is straight from Brandon, and his team at Warbonnet Outdoors. 
 
 The colour is Dark Foliage Green and it comes with a Stuff Sack.
 
View the full product details on the Warbonnet Outdoor website.