The previous iteration of the Rab Latok Ultra bivi, this eVENT mountaineering shelter purports 4 season comfort as a single wall, ~3 lb. “two person” tent. Er bivi. Bivvy. Bivy?

Before UK mountaineering manufacturer Rab introduced the Latok Ultra bivi in 2012, this single wall eVent shelter was known as the Summit Superlite Bivi, and at a weight penalty of merely 3 lbs. ± 3 oz. (depending upon configuration) was & is among the lightest mountaineering shelters available on the market. eVENT waterproof/breathable fabric, specifically 3.1oz triple grid 15d ripstop waterproof breathable nylon with a tricot backing, doesn’t technically comply with accepted US standards for flame retardation, and as such GE – owner (via purchase) of the eVENT membrane technology – hasn’t approved release of any shelter that conforms to standardized “tent specifications.” As a result, the Rab Summit Superlite Bivi – and its updated doppelgänger the Rab Latok Ultra – redline the tent spec with a shelter that’s almost tall enough, nearly long enough for a 6′ human to live in comfortably. Almost.

Mountaineering vs. Four Season Shelter
The Summit Superlite and its direct descendant are in fact a bit of overkill for simple, winter camping: it is correctly a single wall mountaineering shelter, per the manufacturer suited for “expedition / self assisted polar and high altitude / summit assault” capable of withstanding extreme weather and wind conditions, with myriad guy points, an apex belay donut, dual crossover pole configuration, and a tunnel vent for belay tie-in and snow collection. The result isn’t a four season ‘tent’, but a “fourth season” shelter I would only use on snow and in inclement winter/polar/mountaineering conditions. That said, on several trips in the Pacific Northwest Gorge & Cascades this season, for a mere 3 lbs. carried I’ve appreciated the nuanced creature comforts that a full shelter provide – chiefly freedom of movement and the ability to keep all of my gear directly out of the snow – that I’ve had to forgo in my previous winter kit comprised of an OR Alpine Bivy + SMD Gatewood Cape.

The Rab Summit Superlite Bivi absolutely crushes the wind machine test

Minimalist Living Space
The lone issue I have with this shelter lay in the cramped quarters provided. Between the “bivi” spec constraints and the trade-offs necessary to keep the weight down near 3 lbs., the dimensions are a bit Spartan for anyone 6′ tall or taller. I’m roughly 6’1″ and while I’m able – barely – to sit up fully atop an inflatable pad such as the NeoAir All Season pad if leaning a bit forward, it’s only marginally possible for me to lay comfortably stretched out head to toe without angling my pad diagonally across the Superlite floor.

Sufficient room for one w/winter gear; two would need to be really comfortable w/one another

Despite the tight quarters I’ve been able to sleep quite comfortably in this diagonal fashion: the primary need to do so isn’t so much that I couldn’t stretch out my legs, which I could and don’t particularly need to as a side-sleeper; rather, it’s to keep one’s face from bumping up against the relatively steep end walls that practically ensure that anyone over 6′ in height sleeping at right angles to the door may awake find their nose out the rear tunnel vent.

With a height of 70cm (27.56 inches) it does as I noted previously provide just barely enough head room to sit up, kinda, atop an inflatable pad without hitting the crown, but it’s considerably shorter than the ~40 inches of peak height found in many 3 & 4 season tents. In my experience however this is important mostly in a 2 person tent when conditions may force you and a companion to spend extended hours in shelter, and for solo use I’ve been able to dress, eat, treat water – even employ indoor plumbing – without much fuss, and for me the peak height was a minor issue.

Features & Benefits
The Rab Summit Superlite Bivi is incredibly easy to setup, utilizing 2 fairly standard shockcord/8.84 mm (0.35″) aluminum poles in a crossover configuration, with Velcro loops to keep poles in place in the interior, and four very tough pole pockets in the corners. This is key because you’ll put a lot of torque on those corners as you slide the poles into place. I’ve found the easiest way to set the Superlite up is to do so standing, with the bivi rear above you: do one pole corner to cross corner first, slide into correct position and secure with the Velcro tabs, and then repeat with the second pole. With this method I’ve been able to get the Superlite into freestanding position, ready to stake/guy out in less than five minutes, wearing gloves.

Takedown tip: undo the Velcro tabs first thing on your last morning when you’re warm and you can do so without gloves or mitts – it won’t affect the setup integrity unduly and it will be immeasurably easier to get the poles out w/o having to get back into the bivi.

Key Features:

• True ultralight mountaineering/winter solo shelter weighing an average of 3 lbs. 2 oz. in typical winter backpacking configuration
• Single, amply sized gear pocket near door is more than adequate for basic organization
• Lightweight aircraft aluminum stakes, minimum of 6 required to stake out securely
• Highly breathable and legitimately waterproof eVENT construction and subtle ventilation provides for minimal condensation and excellent wind protection in conditions featuring moderate to heavy snowfall in sub-freezing temperatures
• Spacious enough for two NeoAir All Season pads to fit side by side in conjunction with a double winter quilt (and a happy couple) but likely zero gear. Adequate room for a solo user + his or her gear
• The door functions well inasmuch as it is raised several inches as a “porch” to keep spindrift out*
• Easy setup and takedown

Noted Issues:

• A bit cramped, particularly for taller shelter residents
• Included V stakes perform and anchor well in hard snow; in powder true snow stakes such as SMC Sno-Tent stakes or deadman anchors are recommended
• Sharp wall angles in front necessitates serious shaking to remove snow when entering/exiting lest you fill the front of your tent with snow; the identical wall angle to the rear requires taller users to sleep diagonally to avoid pressing one’s mug against the back wall
• The door tends to catch on the protective flap and isn’t easy to open one-handed, particularly with mitts*
• No vestibule (or usable interior space) for multiple user gear

Sheds snow extremely well

Specifications:

• Highly breathable Exchange Lite™ eVent® fabric
• 10000mm laminated lightweight ripstop nylon waterproof bathtub base
• Internally pitched DAC 8.84mm aluminium poles
• 1 sealed belay donut loop tie in point
• Rear snow collection/belay tie-out drawcord porthole
• 1 internal pocket
• Glow in the dark zip pullers/reflective tie-out tabs (a nice feature)
• Aluminum pegs: 16
• Guylines: 6 included w/tensioners. High-vis, strong, lightweight. May replace w/Dyneema Ironwire
• Guy-Out points: 13
• Average weight: 3 lbs. 5 oz / 1500 g (mountaineering configuration)
• Max Inside Width: 47.2 in / 120 cm
• Max Inside Length: 87.4 in / 222 cm
• Peak Height: 27.5 in / 70 cm
• Doors: 1
• Freestanding: Yes
• Seam Taped: Yes

Conclusion: RECOMMENDED
The Rab Summit Superlite Bivi, now essentially known as the more predictably colored and more interestingly named Latok Ultra Bivi, is an excellent ultralight single wall minimalist mountaineering shelter worthy of winter adventures above and below the timberline. It’s not ideally suited for two people, taller folks, or claustrophobic types, but it remains a unique UL solo shelter for those seeking summit-worthy protection in a ~3 lb. package.

Note: the Author acquired this equipment at his own expense and was not compensated by the manufacturer in any way.

RAB SUMMIT SUPERLITE BIVI. MSRP $495. US.RAB.UK.COM