You won’t find many lighter and packable bivy bags than this one from Sierra Designs. It weighs just 450g – I’ve owned camping pillows that are heavier than that. I’d say it’s no bigger than a 24 oz Hydro Flask too.
Weight and packed size isn’t everything though, because you also want a bivy bag to keep you well protected from the elements and from any cold and wet ground. Well, good news. This ranks pretty well there too
Materials and Details
This is actually based on an original design that’s been available in the States for some time now, it’s just had a few tweaks to make it more suitable for a northern European crowd. Sierra Designs have upped its waterproofing to make it better suited to the damp conditions we’re so lucky to get here in the UK and they’ve also given it a more muted colour scheme to appeal to the general British preference for shelters that create a degree of stealthiness.
Pros: Very light and packable
Cons: Basic in terms of features, fabric is on the thin side
On the base, there’s a 30D nylon ripstop fabric while on the top a slightly thinner 20D nylon ripstop is used. These fabrics both feel very light. To give you an idea of what it feels like, I’d say it’s comparable to the fabrics that 2.5-layer waterproof running jackets are made from.
The main opening is a zipped U-shaped flap that comes down to just short of halfway down the bivy making access in and out relatively easy to get in and out of. The zip is a basic one with no water resistant laminated or treatment but it does have a storm flap to cover it.
There’s also one little zipped flap that opens up to reveal a mesh window. This is designed to serve as an air vent when you need to hunker down inside the bag when there are insects about. The mesh is fixed so you can’t open this up.