The Gear Loop is supported by its readers. When you buy through links on our site, we may earn an affiliate commission. Learn more

(The Gear Loop) - A lightweight insulated (or puffer) jacket should be a wardrobe staple for anyone who likes to mess about in the Great Outdoors during the chillier months, as the insanely packable garments provide a staggering amount of warmth and protection from the elements for something that can be stuffed into a large pocket. We collated al ist of some of our favourites here.

Originally designed as mid-layers for those adventuring in sub-zero climates, they’ve now become the go-to jacket for anyone that wants the versatility when out hiking, or is venturing to those places where wild swings in temperature require the handiness of an easily stowed jacket.


The Rab Infinity Microlight Down is one of the brand’s best-sellers, as it takes much of the technology from the bulkier Infinity range and whittles it down into an extremely lightweight and malleable package that’s simple enough to stash when necessary.

The Gear LoopRab Infinity Microlight Down Jacket review photo 1

It uses a combination of Gore-Tex Infinium fabrics and pre-treated recycled down to offer more water-proofing than its rivals, allowing it to act as an outer layer in all but the most extreme conditions. If there’s just one jacket to see you through the winter months, this is probably it.

Our quick take

This is one extremely comfortable, breathable and warm insulated jacket that does a great job of providing all the protection from the elements that most will ever need. The use of quality down means it remains warm in freezing conditions, while a relliance on Gore-Tex Infinium for the outer adds brilliant wind and rain protection.

Most will find it quickly gets too hot on a strenuous hike, which is fine, because it can easily be packed down into a provided stuff bag and carried, clipped on to a rucksack or jammed inside a larger pocket. 

The Gear LoopRab Infinity Microlight Down Jacket review photo 13

Little touches, such as the elasticated cuffs and soft fabrics in the "garage" (the area around your mouth when fully zipped up) only serve to add to the comfort and convenience, while breathability is also excellent. It’s far less sweaty and clammy than some of the other jackets we’ve tried.

The fit errs on the tight size, though, and there’s not a lot of stretch for those thinking of using it as a focussed climbing jacket, but there are very minor black marks on a largely squeaky clean record. 

This jacket was kindly provided by Trekkit for purpose of review.

Rab Infinity Microlight Down Jacket review: warmth without the bulk

Rab Infinity Microlight Down Jacket

4.0 stars
  • Athletic cut
  • Recycled down
  • Performs in the wet
  • Basic colour range
  • Sizes come up small


In the Loop

Here’s what you can expect from the Rab Infinity Microlight Down Jacket:

  • A featherweight 452g overall weight in medium sizes
  • 700-fill power recycled down with Nikwax hydrophobic treatment 
  • Helmet-compatible and adjustable hood with reinforced peak
  • Tough YKK zips
  • Stretchy cuffs for gloves and easy watch glances
  • Stuff sack included
The Gear LoopRab Infinity Microlight Down Jacket review photo 4

Design and features

The jacket sports a fairly athletic fit, meaning it eschews the boxier and more basic cut of some insulated jackets out there. It does a good job of moving with the body, too, making a great companion for hiking and mild scrambling.

It’s arguably not quite stretchy enough to act as a proper climbing jacket, as it can be a little restrictive when lifting arms above the head or going for those longer reaches. This is partly down to the, erm, down, which is of a very high quality 700 fill power (FP). 

In essence, the higher the FP number, the better quality the down and the more it "lofts" or puffs up. Very rarely do things go above 900, which gives you a good indication of just how warm this jacket is going to be.

The Gear LoopRab Infinity Microlight Down Jacket review photo 9

That down is also cleverly mapped into very narrow baffles, which is designed to maximise on warmth but also improve the packability and flexibility of the jacket. The down is 100 per cent recycled and treated at source with a Nikwax coating to ensure it performs better when damp.

This isn’t a 100 per cent waterproof jacket, but we’d argue that it gets pretty darned close and it’s certainly one of the most versatile insulated jackets we’ve worn, easily acting as the only layer you’ll need on an unpredictable, chilly day.

Zips are of the chunky YKK variety and feel like they will withstand a lifetime of abuse, while all of the pullcords are made form tough nylon with ergonomically designed plastic toggles. These are really easy to locate and use with gloved hands.

The Gear LoopRab Infinity Microlight Down Jacket review photo 6

The hood feels excessively tall, but this is because it is compatible with most climbing helmets, allowing it to slip over the top and keep heads warm when out climbing or scrambling over tricky surfaces.

A fairly industry standard drawcord adjustable hem means it’s possible to seal things up during particularly windy weather and snow storms, while elasticated cuffs are an additional neat touch. These are really easy to pull over a chunky adventure watch, but also remain snug over thick gloves.

Performance in the wild

The jacket nails two important briefs straight off the bat: it’s light and ridiculously warm. That’s all you want, isn’t it? For most outdoor pursuits in the UK, it will be all the jacket you’ll ever need, with very few occasions where a fully waterproof outer is required. 

The Gear LoopRab Infinity Microlight Down Jacket review photo 8

We found it kept the worst of the rain out and dried extremely quickly when it did get soaked. What’s more, the down remained nice and fluffy in the damp, ensuring it carried on with its warming duties without getting bogged down and losing its fluff factor.

There are two deep hand pockets in the usual places, although these aren’t lined, but the inner is so soft you probably won’t notice. there’s an additional zip pocket on the chest, which is perfect for stashing a phone or map.

The only thing we found is that this chest pocket tends to be fairly open to the elements and typically takes the brunt of the wet weather, so it’s not the best for storing anything you don’t want to get damp. A separate, weather-proof inner pocket would be a nice addition.

The Gear LoopRab Infinity Microlight Down Jacket review photo 11

Another downside we found was with the fit, which looks great but doesn’t leave much room for layering up. Stick a bulky jumper on underneath and it gets a bit restrictive, so size up if you’re a fan of chunky woollen cable knits.


To recap

This is one of the best selling down-filled insulated jackets and for good reason. It’s light, extremely packable, breathable and performs well even when it gets soggy. It’s quite pricey, mind, but the cost goes towards cutting-edge fabrics and clever Nikwax hydrophobic treatment to ensure the down word in wet conditions.

Writing by Leon Poultney.