Mountain Equipment Graviton Jacket 2009

With waterproofs there’s a dilemma: to go for light weight, or comfort and practicality. But is there a top that does it all? The latest offering from Mountain Equipment (ME), the Graviton Jacket, is certainly up for the challenge.
Weighing 290g (women’s 12), the Graviton is just 15g heavier than ME’s lightest waterproof (the Particle Jacket)
but those few extra grams allow it some extra features.
For those used to Gore-Tex Paclite, what is instantly noticeable is the supple feel of the Drilite 2.5 layer fabric. Like Paclite, the only drawback with a 2.5 layer fabric is that any condensation which forms will be more evident than with a 3-layer material, such as Gore-Tex Pro Shell. To counter this, ME has added pit zips, to allow underarm venting – something its lightest jacket lacks.
Another extra feature is a front pocket (in addition to the two chest pockets) that is big enough to hold a map, GPS, guidebook or a pair of gloves. All the pockets are mesh-lined, which is great for venting and keeping things light, but they are not as watertight as sealed ones – particularly as, in this case, the zips do not have a double stormflap over the top of them.
The main zip also only has a single stormflap, which means that the Graviton will not keep you as dry as those with a double flap. But the reinforced shoulders, another feature that has made this jacket fractionally heavier,
also make it more durable.
The main difference between the Graviton and the lighter Particle Jacket is the hood size. To cut down on weight the Graviton’s is smaller and thus does not fit over a helmet. But seeing as the majority of hill-walkers don’t use helmets this will not be an issue for most people. Also, research by Leeds University found that jackets whose hoods are helmet-compatible leak more easily than those whose hoods aren’t, mainly because of the bunching effect that occurs when you readjust the hood size to fit closely to your head. This means that with the Graviton hood you get a close fit, and I found very little adjustment was required to give a good seal to my face. A brushed polyester chinguard makes the hood comfier, and the fact that you can roll it down and secure it with a Velcro fastening is a bonus. There is also a wired peak for restructuring the hood after pulling it out of its stuffsack. The light weight meant I didn’t get too hot, and the pockets were easily accessible when wearing a rucksack. 
 It’s easy to be sceptical when promised functionality and a lightweight design, but in Snowdonia in the drizzling rain I was impressed with the Mountain Equipment Graviton and – even more importantly – dry. 


Outer 2.5 Layer Drilite Ultra
Inner none
Fabric waterproofness very waterproof
Fabric breathability very breathable
Sizes 8-16 (women’s ); S-XL (men’s)
Weight 290g (women’s size 12)
Made in China
Stockist details – tel. (0161) 336 5020;

Verdict: The Mountain Equipment Graviton is more durable than other lightweight jackets courtesy of the reinforced shoulders; great-sized pockets and a practical hood for the majority of hill-walkers; very competitive price and weight for performance. But it won’t keep you as dry in really wet weather; if you regularly need to use a helmet you’ll need to go for something with a bigger hood. Overall, a great lightweight jacket for spring and summer with more features than others in its weight class.


Review by Phoebe Smith
First published in Trail magazine Spring 2009