Tundra Pure -5 2010

Staying warm is about placing the most efficient insulation in the right place around your body. Tundra places extra down at the foot so you don’t have to wear socks in this sleeping bag! Equally it uses down that is collected from the bird’s nests rather than being plucked. The end result is happy geese and warm campers.

Design
The Tundra Pure -5 has been designed to provide maximum warmth for minimum weight, and that means making the most of your insulation. So this bag uses every trick in the design book. Firstly there is the down itself. The use of down that is collected from the nests of mature geese that are five years of age results in large fully developed down clusters. According to Tundra, down from birds used in the food chain and killed at around four weeks is not fully developed and therefore, it cannot achieve a high fill power. This bag used down with a fill power of 860 when tested to European standards, which is better than most of the other bags tested here.
But down loses its insulation if it gets wet, so the head and foot is made from waterproof material. This means that when squashed against the end of a condensation-soaked tent, the down should stay dry and maintain its efficiency. However the bag does not have a side baffle so the down can be moved across the bag if required.

On the hill
The Pure -5 is very compact when squashed into its stuffsack, which has two drawcords to make sure it really compresses well. It’s not the lightest here, but it is still very lightweight and ideal for stashing in a rucksack. The bag ‘lofts’ (fluffs up) easily, but as there is no side baffle to prevent down on the sides migrating, you do need to shake it out to ensure down is evenly spread. There is a small zip baffle and the zip did not snag in my testing. There is also a good shoulder baffle to lock in trapped warm air. When you get inside the bag it feels very comfortable. The foot is wedge-shaped so the down does not get compressed around your toes or heel. Also the hood fits well and is easily adjusted with a drawcord. 

In the lab
The Tundra Pure -5 gained a rating of 10.1 TOG / -10 deg C. This is warmer than Tundra states but this allows for 3-season use even after some degradation has taken place over time. Remember that the bag is warmer at the foot as we only test the chest area.

Size 220x80x55cm
Outer fabric Micro 20 nylon; waterproof at foot and head
Inner fabric micro nylon supersoft
Fill weight 400g ethical goose down
Fill power 860
Lower comfort temp rating -5 deg C body (-10 in head and foot)
Trail temp rating -10 deg C
Packed size 37x18cm in stuffsack; 27x18cm compressed
Weight bag 808g; stuffsack 40g
Made in Poland
Stores across UK 12
Stockist details tel. (0161) 432 0319; www.tundrasleepingbags.com

Verdict
The Tundra Pure -5 uses waterproof material at foot and head; enhanced foot space with extra insulation; ethically sourced down, well-fitting hood. But there are no side baffle so users need to ensure down is correctly distributed; others felt a little warmer; zip snags easier than others. In conclusion, it’s an excellent ethical bag with enhanced performance features at the foot and head that won ‘Best value’ in our test.

Review by Graham Thompson
First published in Trail magazine Spring 2010