This has been accomplished because of the DUCKSBACK material. The original Single Person Bivi Shelter needed a fly to cover the insulation. The fly is eliminated due to the use of the DUCKSBACK material.
Many years ago, I was asked by a member of the Mazama climbing club (the oldest in the country) if I could make a bivi bag with an insulated top. I made a product for them that was used successfully on a climb of several mountains in South America. Doing work for the Marines at that time led me to show it to them. They had me make a change here and there and tested the "bivi's" in Norway. The results were all of a positive nature. Finally, I received a call from the Air Force. They required a multitude of changes. The end result is what we now produce with one exception: the forward wind flap. That came about because of a local individual.
The culmination of three years of development produced the most efficient single-person shelter available. The top section over the body of the shelter comes with an option to be is insulated, and therefore can be used without a sleeping bag in mild conditions (+45° Fahrenheit and higher). When used together with any Wiggy's bag, you can expect an additional 20° lower than the bag is rated. The chest section, when purchasing the insulated option, is insulated with our exclusive Lamilite L-6. It is vapor permeable. General rain and snow activity does not penetrate.
Other features include an Easton aluminum shock corded pole, built in stuff sack (12" x 15"), mosquito netting, and steel stakes. The pop-up hood stands 24" high and the whole thing weighs 2.5 lbs.
Quality craftsmanship, excellent results. I've been using the winter bivy to sleep under the stars at 7,000 feet in northern New Mexico, high 20's, low 30's. Blissful, warm, wonderful night's sleep.
– Todd R. Doherty
I teach Hunter Education and the products this company manufactures are high quality and reliable. Wiggles also stands beside whatever they make. We recommend his products because, without a doubt, they produce remarkable products at reasonable prices.
– Claudia Daw
Mine is the older version with the separate rain fly over the insulation. When I ordered it I asked for extra material which was graciously provided. This was used to modify the bivi to fit my preference for rectangular bags. I've learned to trust Wiggy's designs so other than seam seal where the bottom is now pieced, the rework is as close to OE as i could make it. When traveling fast and light (one person, one Concours, too few days) this is the best thing for stealth camping that I've ever found. Camp make/break time is shorter than anything but the Iron Butt Motel. If the morning is dryish you roll the whole rig up together with your pad and sleeve it in an appropriate cylinder. You can have it bagged and on the back seat in 90 seconds if motivated awake by the sound of thunder. Add time to squeeze out an air mattress.
It works as advertised, raising your bag insulation about one step, and providing significant wind block. If hot, the bivi gives you the option to hang a leg out without feeding the locals. The hoop (optional use) will keep bug screen off your face and makes weather changes in the night something that you can adjust for without actually waking up. The only gripe I ever did have was that the rain fly flaps in the wind and can be rained under in the wrong conditions. Assuming you are using lamalite layers this is more annoyance than problem. The new bag will have this covered. And it comes in colors other than black...
– Bruce Halleran, IBMC