Like our quilts the objective of our ultralight weight down sleeping bags is to keep you warm with the lightest possible equipment weight. The key to an ultralight weight sleeping bag is the same as for the quilts; use light fabrics and high fill power down. The materials that we use are 1.0 oz/yd2 20D nylon and 800 fill power, water-resistant goose down. We also incorporate full length, 72 inch, two way separating, number 5 YKK coil zippers. As we mentioned earlier, we prefer quilts above freezing and bags below. Since the bags are generally used in colder weather, you will likely be wearing more clothing in the bag and you may have taken some articles into the bag with you for various reasons. This means that you will need a little extra room in the bag. There is nothing worse that a bag that is so tight that you can hardly move your arms. Our bags have an inner girth at the shoulders of 63 to 64 inches. We feel that bags that are less than 60 in. in girth are just too tight for most people. Buying a cold weather bag that is too constraining is a mistake that you don’t want to make.
A key feature of our bags is that they are differentially cut. This means that the circumference of the outer shell of the bag is greater than the circumference of the inner lining. Many bags are constructed with the inner and outer girth the same. In these bags, if you push out with you elbow, the inner lining will push against the down compressing it against the outer shell. Essentially the insulation goes to near zero thickness. This cannot happen in a differentially cut bag. This advantage is not without a price, since the manufacture of a differentially cut bag is more complex requiring additional assembly time. Other design features to note are the side block baffle that keeps down from shifting from the top to the bottom of the bag and vise versa. The zipper draft flap is an extension of the bag, not a single tube that runs the length of the zipper as found in most bags.
We place our zippers where you can reach them. It has become trendy to move the zipper to a lower point on the side of the bag, supposedly to reduce heat loss through the zipper. This puts the zipper in a position that is almost impossible to reach. Try lying on the floor and taking your right hand and touching the floor over your left shoulder and moving it down the left side of your body while still contacting the floor. If the bag has good insulation behind the zipper you can place it within reach without fear of heat loss. All our bags are made with the zipper on the left side. Right zippered bags are available by special order only.
We offer an optional collar (please contact us for a quote) that creates two compartments in the bag, one for your body and one for your head. We are personally not big on collars. They add weight without adding any significant warmth and have a draw cord that is either always on the wrong side or you are always tangled in it. In our opinion, one draw cord, the face opening draw cord is plenty. On the other hand, if you breath inside the bag, which we do not recommend under any circumstances, a collar would localize the deleterious effect that this moisture would have on the insulation to the head of the bag.