Outdoor Research Helium UL Bivy

A 511 g single-hoop bivvy in recycled Pertex Shield NetPlus, with a clamshell entry, insect mesh and twin vent flaps.

Weight: 511 g
Waterproof: n/aBreathable hydrophilic laminate, plus dual passive vent flaps
Packed: Not stated by maker

Best price found

£239.99RRP ~~£274.99~~Save £35 (12%)

at Ultralight Outdoor Gear · In stock

Prices checked 7 November 2026. We may earn a commission on these links.

Specifications

Weight: 511 g (18.02 oz (511 g) as quoted by retailers from the maker; Ultralight Outdoor Gear lists 530 g (454 g bivy + 76 g pole, excluding pegs and bag))
Packed size: Not stated by maker
Fabric: Pertex Shield NetPlus, 100% recycled nylon 30D ripstop upper; PU-coated nylon floor; fully seam taped
Hydrostatic head: Not stated by maker (Trekitt quotes 20,000 mm)
Open size: 208 × 66 × 48 cm (length × head width × foot width, per Ultralight Outdoor Gear)
Entry: Zipped clamshell opening
Breathable: Breathable hydrophilic laminate, plus dual passive vent flaps

Fast set-up, small footprint and low profile (Ultralight Outdoor Gear's review; it also sells the bivy)
Full insect mesh and "better-than-basic headroom" from the hoop (same review)
"Blocks wind and light rain well" (same review)
"Condensation is part of the deal": it needs active venting (Ultralight Outdoor Gear's review)
Heavier than the previous Helium Bivy: about 530 g against 479 g, per the same review