"The winter hammock Topcover zips on in place of the updated XLC bugnetting. It is used in cooler weather to cut the wind and trap a little extra heat. It’s made of a breathable, wind and water resistant 20 denier fabric. 
 
It has 2 built-in mesh air vents, one in the peak at the foot end and another near your shoulder that doubles as a window. It works just like the XLC net top but with solid fabric instead of netting. 
 
It will also zip directly to our underquilt protector 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 new winter topcover will only fit the newly updated XLC purchased after October 2017."
 
The above wording is straight from Brandon and his team at Warbonnet Outdoors. 
 
The colour we currently offer is Dark Foilage Green or Olive Green.