The UltraShield is HighSierra Co.'s ultralight emergency and fast-and-light bivy — an 8.5-oz sack that turns any sleeping bag into a weatherproof system. Constructed from a 3-layer eVent DVMatrix fabric, it offers genuine waterproofing (10,000mm HH) with enough breathability to prevent the condensation trap that plagues cheaper aluminized-foil bivies.
The YKK waterproof zipper opens from head to foot for easy entry and internal condensation management. A small mesh window at the head end allows ventilation while keeping precipitation out. Stakes through the built-in loops at the foot end anchor it in high wind.
Pair it with a 35°F bag to extend its rating to 20°F conditions — one of the most weight-efficient warmth upgrades available. At under 9 oz, there's no reason not to carry it.
- Fabric: 3-layer eVent DVMatrix (top), 20D ripstop (bottom)
- Waterproof rating: 10,000mm HH
- Weight: 8.5 oz | Packed: 4x3 in stuff sack
- Interior: 84x30 in | Fits sleeping bags up to regular length
