Zeta Primaloft Half Bag

A Primaloft-filled Half Bag for mountain bivis or emergency use. Team with the warm jacket you already carry. Camp down to 10°C (50°F) and bivvy down to 5°C (41°F).*
Typical Operating Temperature
Guideline minimum temperature. Sleeping Bag TOT: you should get a night’s sleep, under normal circumstances. Clothing TOT: you should feel warm enough, assuming low/moderate activity. Sleep System TOT: relates to full system. For more details, see our Technical Briefing.
10°C / 50°F
Weight
For clothing, weight is for size: M. For sleeping bags, weight changes with selected length/width. N.B. there may be some variation in the weights of finished products.
395g / 14oz
Price
£292.00
Zeta Primaloft half bag

Combined with a suitable insulated jacket, it forms a versatile, light, but still reasonably warm sleeping system. Ideal for fast and light alpine stuff.
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Features

  • Insulation: Primaloft Gold (133 gr/m)
  • Outer fabric: Water-resistant Ultrashell. An excellent balance of weight, water-resistance and breathability
  • Super-light MX inner fabric
  • Edge-stitched for maximum loft
  • One size fits all. Long enough to cover an insulated jacket at the waist
  • Length: 110cm at the front. 130 cm at the back
  • Stretch cord with cord lock to cinch at the waist
  • Reflective strip for night location
  • Oval foot piece for comfort
  • Stuff sac size: 13 x 21cm*
  • Charcoal outer, black inner.
  • Option:
    • Waterproof Dri-LX outer fabric shell (+175g)‡

*Please note: We make our stuff sacs big enough to allow fairly easy stuffing rather than reducing the bag to the tightest minimum.

‡Please note: The optional waterproof Dri-LX outer provides an extra seam-sealed outer shell to the bag. While a shelled half bag is not designed to be used alone in heavy rain (water will find its way in) the shell does protect the bag when it is used outdoors without a tent.

Description:

Camp down to 10°C (50°F) and bivvy down to 5°C (41°F).*

The logic behind half-bags (Pied d'elephant to oldies) is so sound that the idea is back. If you're wearing a warm jacket already, all you need to spend the night out is something to keep your legs warm and there's no lighter way to do that than to use a half-bag.

The Zeta half bag is a synthetic version for when the cold also threatens to be wet. In our experience Primaloft Gold synthetic insulation absorbs water much more slowly than other synthetic waddings, a marked advantage in cold, wet conditions. 

Useful for everything from the Cuillin ridge to a summer Alpine Bivi. For a lightweight trip or carried for backup the half bag is the lightest answer.

The optional waterproof Dri-LX outer provides an extra seam-sealed outer shell to the bag. While a shelled half bag is not designed to be used alone in heavy rain (water will find its way in) the shell does protect the bag when it is used outdoors without a tent, for example in a snow-hole or under a tarp.

*Note on Temperature Ratings

We have given two separate TOTs (Typical Operating Temperatures) for this half-bag.

  • 'Camp' is for the times people might want to use it for lightweight camping instead of taking a sleeping bag (an appropriate jacket and ground insulation is assumed): this is a standard TOT, meaning you should be able to get a good night's sleep under normal circumstances.
  • 'Bivvy' gives a range of temperatures from the usual doze level down to the point beyond which you're liable to be awake and getting cold. Again an insulated jacket is needed.

All these figures assume you are wearing normal clothing inside the half-bag. Any insulated kit like down trousers and down socks will improve the TOT.

 

Dri-LX (weight: 64 gsm)

At just 64gsm, Dri-LX is our lightest 2-layer breathable waterproof rip-stop nylon fabric. Its remarkably low weight not only makes for a lighter load, but also reduces pack size. Its excellent waterproofing qualities are in part due to how it can be taped at the seams to create a waterproof shell for sleeping bags and clothing.

Ultrashell (weight: 40 gsm)

One of the lightest of PHD's coated materials. This ripstop nylon provides complete wind block and good water resistance at minimal weight. Ultrashell gives an excellent upgrade to performance with very little weight penalty.

Superlight MX fabric (weight: 32 gsm)

A mini-ripstop nylon with excellent tear strength, MX is the pick of the superfine 15 denier downproof materials. We have tested lighter fabrics, but most have had significant drawbacks, while our confidence in MX is based on several years of extensive use in both our ultralight and our high mountain gear.


Primaloft Gold®

Primaloft Gold® is the ideal microfibre insulation. Ultrafine fibres produce an insulating core that is incredibly soft, lightweight and water resistant. In our experience it absorbs water much more slowly than other waddings, a marked advantage in wet-cold conditions.

The nearest of the synthetics to the feel of down, yet tougher than you would expect. Primaloft Gold® offers the best warmth/weight performance in the Primaloft range


Combined with a suitable insulated jacket, it forms a versatile, light, but still reasonably warm sleeping system. Ideal for fast and light alpine stuff.
OutdoorsMagic Review
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