How to Choose an Alpkit Insulated Jacket

How to Choose an Alpkit Insulated Jacket

By Alex Guerrero

If you don’t know your Filoment from your Fantom, then fear not. We’ve put together a brief AlpDictionary of our nine insulating outer layers so you can find what you need to help you conquer the cold . And if words like fill power, PrimaLoft® and micro-baffle all sound a bit like gibberish, then you might need our ultimate guide to down jackets and synthetic insulation.

A Brief Overview

  1. A quick comparison
  2. Sierra PrimaLoft® vest
  3. 0Hiro PrimaLoft® jacket
  4. Talini PrimaLoft® jacket
  5. Heiko PrimaLoft® jacket
  6. Katabatic PrimaLoft® jacket
  7. Halogen ultralight down jacket
  8. Filoment micro-baffle down vest
  9. Filoment micro-baffle down smock
  10. Filoment micro-baffle down hoody
  11. Fantom down jacket

A Quick Comparison

Product Men's M, grams Women's 12, grams Fill
Sierra 273 246 60gsm PrimaLoft® Gold P.U.R.E
0Hiro 690 630 PrimaLoft® Silver Hi-Loft Ultra (Body: 120gsm / Arms & Hood: 80gsm)
Talini 390 340 PrimaLoft® Silver ThermoPlume® with Cross Core Technology
Heiko 344 293 60gsm PrimaLoft® Silver Eco
Katabatic 455 400 PrimaLoft® Gold Active Eco, 60 gsm
Halogen 255 225 800FP down Downtek Hydrophobic Duck Down
Filoment Vest 240 210 630 FP down
Filoment Smock 375 345 RCS certified recycled down, 630FP 80/20
Filoment Hoody 405 358 630 FP down
Fantom 642 518 650 FP down


Sierra vest

What is it: PrimaLoft® Gold gilet with breathable fleece panels. Full zip for the “am I too hot? Or am I too cold?” days. With zipped chest pocket and two zipped hand pockets.

Good for: working hard on the hills, crags and trails. The Sierra leaves your arms free to reach for drops or holds, whilst keeping your warmth where you need it most.

Sustainability: The insulation is 100% recycled polyester and the fleece panels are 92% recycled polyester, coming from sources like old plastic bottles. The nylon fabric is also 100% recycled and made using fabric scraps and leftover materials from nylon manufacturing.

Designer’s notes: "We were very excited to be able to make one of the first garments on the market using PrimaLoft® P.U.R.E.™ technology. This technology goes beyond using recycled materials, reducing carbon emissions throughout the whole production process – and all without sacrificing any performance!"

0Hiro Jacket

man wearing 0hiro

What is it: A superhero below 0°C and master of moist maritime winters – the perfect UK winter jacket; our warmest synthetic layer, using lots of lofted PrimaLoft® fill and a bomber outer fabric. It retains over 85% of its insulating ability when wet! It’s got a helmet compatible hood, a full zip and four pockets for stashing snacks (…or hats and gloves).

Good for: Unbeatable damp-resistant warmth; an outer layer for low intensity activities with a risk of drizzle or sleet; burrowing through snowy gullies in wind-blasted Scottish winter.

Sustainability: 100% recycled polyester liner and 70% recycled PrimaLoft® insulation. Nylon 6,6 outer to last for seasons and PrimaLoft® Hi-loft Ultra survives repeated compressions for longer. It also uses a completely PFC-free DWR treatment so we can say “see ya later” to potentially harmful nasty chemicals.

Designer's notes: "The 0Hiro is a real get-out-of-jail free card when unexpected weather hits: we've added a 5K/5K waterproof membrane to the outer to give you extra time to get off the hill warm and dry."

Talini Jacket

Man wearing Talini

What is it: A passport to ultimate worry-free warmth; light and compressible jacket using innovative down-imitation fill from PrimaLoft®; a full zip windproof outer jacket or a toasty mid layer. The lightweight, hoodless Talini has got zipped handwarmer pockets and a zipped chest pocket.

Good for: Packable rest-stop warmth throughout the year; an outer layer for cold and windy hill walks; an ultra-warm mid layer when the weather gets really nasty; damp British camping!

Sustainability: The outer fabric is treated with a C0 Durable Water Repellent finish, which is completely PFC-free – no nasty chemicals

Designer's notes: "PrimaLoft® ThermoPlume is the closest you can get to down levels of performance: the synthetic fill is equivalent to around 600 FP and performs better in the wet than even hydrophobic down."

Heiko Jacket

What is it: ultralight and packable PrimaLoft® insulated jacket. Windproof, warm, and damp resistant.

Good for: packing a punch and packing down into its own pocket. Great for changeable weather and throwing in your bag.

Sustainability: The Heiko jacket is made with 100% recycled polyester for its inner and outer fabrics. It also uses PrimaLoft® Silver Eco, a 100% recycled polyester insulation, for the fill.

Designer's notes: "With a PFC-free DWR and 100% recycled fabric and fill, the Heiko is our most sustainable jacket yet. And it's not just any recycled polyester fabric. It's a fabric that feels amazing next to the skin. We've even used it as the lining in our sleeping bags!"


man wearing katabatic

What is it: The jacket you’ll never take off; toasty PrimaLoft® Gold Active fill and air-permeable fabrics for maximum mid layer breathability plus wind-resistance for outer use – two jackets in one! The Katabatic has a simple insulated hood, an adjustable drawcord hem and 3 zipped pockets.

Good for: Working up a sweat, slogging up cold and windy hillsides; under a shell when the weather gets spicy; unrestrictive warmth for scrambling; high effort activities in changing conditions.

Sustainability: PrimaLoft® Gold Active uses 45% post-consumer recycled content to increase its sustainability without compromising performance.

Designer's notes: "If you own just one synthetic insulated jacket, this should be it. No more boil-in-the-bag feeling when you’ve left it on too long: the breathable fabric and insulation work as hard as you do."

Halogen down jacket

What is it:an incredibly lightweight technical down jacket for lightweight fanatics.

Good for:when keeping warm for the smallest weight and space penalty. Take the Halogen and leave room for another pair of socks!

Sustainability: The Halogen jacket is made with 100% recycled nylon outer fabric and a PFC-free DWR.

Designer's notes:: "Our most technical and lightweight jacket yet, we had bikepackers, hikers and alpinists in mind when designing this."

Filoment Vest

woman wearing filoment vest

What is it: Light and packable 630FP fill power down gilet using 100% recycled fabric and fill. The full zip, 3-pocket Filoment keeps your core insulated when weight and freedom of movement are your top priorities.

Good for: Layering up and packing down. Stuff the Filoment in your rucksack for warmth and freedom of movement on the go.

Sustainability: We’re now using PFC-free DWR treatments. They’re non-toxic and don’t build up in the environment, so we’re pretty pleased about that. The Filoment also uses 100% recycled nylon fabric and RCS 100-certified recycled down!

Designer’s notes: “Don’t neglect the importance of your core when you’re trying to keep your extremities warm. Design Tech Gabe always goes for a Filoment vest first when trying to save his freezing hands when winter climbing.”

Filoment Smock

What is it: the latest addition to our Filoment down jacket range, the smock is an easily layerable pullover half-zip.

Good for: stashing in your bag, throwing on, and keeping warm and uncluttered under climbing harnesses.

Sustainability: The Filoment smock's made with 100% recycld nylon on the inner and outer, and is filled with RCS certified recycled down. Like all the DWRs in our range, it's PFC-free.

Designer's notes: "The smock is something so supremely comfortable, you won't want to take it off".

Filoment Hoody

Man walking with Filoment hoody

What is it: The feather-lite champion of packability; a micro-baffle down jacket with a ridiculously small pack size for its warmth; a low-profile outer jacket or sub-zero mid layer.

Good for: Fast and light mountain raids; packing away into backpacks and bikepacking bags for cold evenings in the tent/bothy; low-bulk warmth for UK winter/alpine summer scrambles.

Sustainability: Downtek PFC-free Hydrophobic down and a PFC free DWR-treated outer fabric. Responsibly sourced (RDS-approved) Down.

Designer's notes: "There's a reason why you see so many people in micro-baffle down jackets: they're the holy grail of warmth, packability and ultralight weight – they really are hard to beat for versatility."


Climber wearing Fantom down jacket

What is it: The cold conqueror; the warmest jacket in our family, with a lightweight ripstop outer to pack neatly into rucksacks and mountaineering-ready features for altitude adventures. It’s got chunky baffles to keep you snug subzero, a helmet compatible hood and a longer cut to keep your bum warm! Despite its next-level warmth, it’s got a great warmth-to-weight ratio and is highly compressible.

Good for: Instant warmth for stationary activities or moving at altitude in extreme cold; belaying in fine conditions; camping on cold, clear nights; between ‘send’ attempts in grit season.

Sustainability: Downtek PFC-free Hydrophobic down and a PFC free DWR-treated outer fabric. Responsibly sourced (RDS-approved) down.

Designer's notes: "Probably the warmest jacket you’ll ever need - you may find yourself wishing it was colder just so you can wear it! We're really proud of little touches like the cosy tricot-lined collar and pockets."

Leave a comment

Please note, comments must be approved before they are published