Justin..... start with a good base layer of merino wool, ( Ullfrotte', minus 33, etc, etc. ), then use some goodwill merino sweaters or Cabelas 80/20 wool / nylon sweater. You can even cut the arms off the goodwill sweaters since you can get them for $3-5 and it will keep your arms from bulking up. I then top with a Asbell zip up no hood and finish with my Gray Wolf Vest that is windlined and Conformax insulated. Toasty down to 5-10 degrees. I would not take anything for my GWW vest, best piece of gear I own for bone cold. Long tail that covers your tail, forearm deep pockets and collar that is taller in rear than front for flipping up on the back of your neck. A few chemical handwarmers and I am good to go for 4-5 hrs. My next purchase is going to be a pair of GWW bibs or pants. I love WOOL !!!