Generator Alpine Insulated Jacket

Insulation Type:
558g (Medium)
Insulation Format:
Woven - Durably Warm

UOG TOP PICK - Generator Alpine Insulated Jacket, a superb jacket made for tackling harsh winter environments. This jacket is packed with features and provides a lot of warmth quickly. We’ve singled it out as one o…

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RRP: £289.99
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UOG TOP PICK - Generator Alpine Insulated Jacket, a superb jacket made for tackling harsh winter environments. This jacket is packed with features and provides a lot of warmth quickly. We’ve singled it out as one of our top synthetic jackets.

Crafted with decades of insulation expertise, Rab's warmest, lightest and most-packable belay jacket excels when the elements are at their worst. With advanced Insulation Type and fabric technology, it’s made for gnarly Scottish winter conditions.

Rab says

Designed for climbing, winter mountaineering and all cold weather adventures, this insulated, weather resistant jacket thrives when the elements are at their worst.

Having spent decades on the sharp end in challenging and bone-chilling conditions, we know that Insulation Type provides unrivalled warmth in wet weather. That’s why we’ve strategically body mapped two weights of PrimaLoft® Gold Insulation with Cross Core™ Technology throughout this jacket for maximum warmth where you need it most. The PrimaLoft® fibres are infused with Aerogel, an ultra-low-density material composed of 95% air that was originally engineered to insulate space shuttles! We’ve combined this highly effective insulator with an outer of durable, abrasion and weather resistant Pertex® Quantum Pro Diamond Fuse fabric, made from diamond shaped filaments that lock seamlessly together creating a snag resistant flat surface. The Generator Alpine jacket offers unrivalled protection from the wildest storms in the most rugged terrain.

The jacket features a two-way front zip with oversized puller, an adjustable, helmet compatible hood with stiff peak, oversized cuffs to accommodate burly winter gloves, an internal stuff pocket for stashing gloves, and tactically positioned, harness-friendly hand pockets. The jacket has articulated sleeves to enable full range of movement and a drawcord hem to adjust the fit.

Our Verdict

Rab have drawn from their decades of experience to make a tough, strong and reliable insulating jacket to shrug off the worst of the winter weather.

This is classed as a belaying jacket, a Belaying jacket for those out of the loop is a jacket to put on over the top of your traditional layering system when you stop in the mountains. As the name implies, when you stop, to belaying someone climbing or perhaps to stop for lunch, your body rapidly loses heat, a belaying jacket is your protection from this rapid heat loss. With that in mind, a belay jacket is built with 3 core principles. It has to be extremely light, remarkably packable, and most importantly incredibly warm.

As its the jacket’s primary function, the insulation is key. Rab has chosen to use Primaloft gold, an incredibly high-quality synthetic insulation. As it’s synthetic, it’s unaffected if/when it gets wet, this jacket isn’t waterproof, but is water-resistant. For the core of this jacket, a stout 133g/sqm of Primaloft Gold insulation, has been used throughout the main torso, and a slightly less insulating, 80g/sqm has been used around the hood, this is for better freedom of movement, but also to stop the insulation impairing your hearing. The Primaloft insulation itself has been treated with Aerogel, and this is the “cross core” technology and is the stuff of science fiction, in fact, it was invented by NASA, so science fact. It’s the world’s lightest solid material, made from 99.98 % air, it’s basically incredibly light and very good at trapping air, which makes it an incredible insulator.

The jacket is on the large size, this in no way means you should size down, it’s designed to be worn with full winter gear on. All of the zips are glove-friendly, meaning they have oversized loops, and the cuffs are large enough to incorporate thick winter gloves. 1 zipped chest pocket, 2 zipped hand pockets, as well as 2 internal pockets provide plenty of space to store items. As you would expect with a belaying jacket the zip is dual directional, to use with a harness or while belaying. The hood is fully adjustable and is helmet-compatible. The hood adjustment points, hem drawcord, and Velcro straps around the cuffs are all designed to be used one-handed by gloved hands.

An incredible jacket, that performs admirably when it’s needed, it packs down small, only weighs 558g ( for the medium) is unbelievably light, and has unprecedented levels of warmth, thanks to the remarkable technology used. I think it’s fair to say Rab has achieved their goal.

- Reviewed by Ultralight Outdoor Gear

In-depth Reviews:


  • Helmet compatible hood with stiffened peak and 2-way adjustment
  • 2-way YKK® VISLON® front zip with insulated internal zip baffle, chin guard and oversize zip pull
  • 1 YKK® Vislon zipped chest pocket with oversize puller
  • 2 large YKK® zipped hand warmer pockets
  • 2 internal open stuff pockets
  • Oversize cuffs with hook-and-loop adjustment for use with large gloves
  • Articulated sleeves for mobility
  • Adjustable hem


  • Small weighs: 540g
  • Medium weighs: 558g
  • Large weighs: 570g
  • XLarge weighs: 602g
  • Fit: Reguar
  • Centre back length (Size M): 80cm/31.5inch


  • Outer Fabric: Combination of 2x 20D Pertex Quantum Pro fabrics 40gsm (Diamond Fuse front/ Recycled back)
  • Lining: 15D Atmos (31 gsm)
  • Insulation: Primaloft Gold Insulation with Cross Core (133gsm Body / 80gsm hood)

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Generator Alpine Insulated Jacket

Generator Alpine Insulated Jacket

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RRP: £289.99
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