The Spring Lake is our "in-between" rectangle bag. Unlike the Summer Lake bag that only has insulation on one side, the Spring Lake has 20 oz. of TechLoft+ on each side, or 40 oz. total. The single layer of TechLoft+ is sewn-thru, but a loose outer improves the thermal efficiency. The Spring Lake bag is great for those cool spring or summer nights when you just need something to
cozy up with.
Note: Weights listed are for the bags only. Add 7 oz. for the stuff sack.