The great thing about the world of camping gear is that there is always someone thinking of ways to improve the gear. I think it’s because when you’re backpacking for hours with nothing else to do your mind tends to focus on ways you could improve your life (I do the same thing when I’m long ride routes). And just when you think a technology might be more or less mature, an innovation comes along that offers a new way of solving a problem.
In the case of Zenbivy, the problem they solve is: how to sleep comfortably in the backcountry? To that end, the company has introduced a new sleep system that’s not quite a sleeping bag and not quite a quilt, but incorporates aspects of both to enhance your night’s sleep.
Zenbivy’s two-piece system consists of a fitted sheet that stretches over your sleeping pad and a top blanket that attaches to this fitted sheet. Functionally it seems similar to a Big Agnes bag if you have experience with these systems (I’ve owned one for years), but designed with a little more flexibility in mind. Here’s how Zenbivy’s marketing describes its system:
Mummy bags are restrictive. They twist and tangle and grab you as you move. They are unnatural, claustrophobic and cause you to slip off the mattress easily. The Zenbivy bed solves these problems. By attaching the quilt to the unfolding “wings” of the fitted sheet, the Zenbivy bed can instantly expand wherever and whenever you need it, allowing you to change sleeping positions with ease. No more constricting, twisting and slipping off your mattress.
From tent to hammock, hostel to van, the Zenbivy bed’s separate quilt adds incredible versatility and allows you to take comfort with you wherever you go. The fitted sheet gives you the ability to fully “tuck in” the quilt when temperatures drop. The integrated hood insulates your head while also serving as storage to keep your pillow in place.
Combined, the quilt and sheet create a complete sleeping bag system that is just as warm and light as a mummy bag, but much more comfortable.
So it looks like you have a little more freedom of movement compared to other sleeping bag designs. It also looks like it would be a good fit for camping hammocks without an underquilt, although I haven’t tried that myself.
Check out the system demo below:
FWIW, the issues you mention with mummy bags and quilts have put me off both of these systems over the years and this looks like an interesting alternative. I see some limitations the system would have; It seems that Zenbivy sleep systems are tied to specific sizes and shapes for sleeping pads, for example. But again, I don’t have first-hand experience with the system, so I can’t say for sure.
You know who can say that for sure? The occupants in the Camping Toys subforum where we have a thread running about the Zenbivy system. If you have additional questions, ask them there or visit Zenbivy.com.