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Autumn is a brilliant time to get outside. The air is crisp, the colours are incredible, and the trails aren’t a muddy mess yet. But this season is also famous for its unpredictable weather, which can make layering a real pain. We’ve all been there: you start a climb sweating in your base layer, only to freeze your butt off on a windy ridge a few minutes later.
That’s where the long-sleeved 1/4 zip top comes in. Forget the crew neck; this simple piece of kit is an absolute game-changer and, honestly, the only base layer you should be wearing from September to November.
So, why is the 1/4 zip so much better? It all comes down to temperature regulation. A crew neck is a one-trick pony—it keeps you warm. But what happens when you start a tough, uphill section and your body begins to generate a ton of heat? You’ve got two options: either you sweat buckets and risk getting a chill later, or you stop, take your pack off, and peel a layer. Both are annoying and inefficient.
The 1/4 zip, on the other hand, is your personal thermostat. Feeling a little warm on that steep scramble? Just unzip it to your sternum, vent all that heat and moisture, and keep moving. Hit a high point where the wind is howling? Zip it right back up to seal in the warmth and protect your neck. It’s an instant, no-fuss way to adjust to changing conditions without ever breaking stride. Trust me, it makes a huge difference.
Now, let’s talk materials. Most great base layers are made from either polyester or merino wool. Polyester is the workhorse—it’s durable, wicks sweat like a champ, and usually costs less. The only downside is that it can start to get a bit… funky… after a long day or two.
That’s where merino wool comes in. It’s naturally anti-bacterial, which means it can be worn for days on end without smelling. It’s also incredibly soft and manages moisture like a pro. While it’s typically more expensive, it’s a brilliant choice for multi-day trips.
A lot of modern synthetic tops now come with odour control treatments, often using silver ions, that help keep them fresh for longer. This is a great feature to look out for, giving you a top that’s tough, wicks sweat, and doesn’t get smelly.
In short, ditch the crew neck. The 1/4 zip is a staple for a reason. It’s the most effective and efficient way to stay comfortable out there, no matter what the autumn weather throws at you.
Are you ready to make the change? The CGR team have done the hard work for you, we’ve picked a great selection for all budgets:
Klättermusen Huge Half Zip Sweater
We’ve been reviewing Klättermusen kit through most of 2025 (they have, however, been around since 1975). It has proven to be well adapted to UK conditions, performs well in all conditions, and looks great. It is at the premium end so you can expect a refined style with top of the range features. The Huge Half Zip Sweater turns the merino/synthetic mix on its head with a 83% polyester/17% wool mix (of which 40% is recycled polyester). The embossed outer is what Klättermusen call their Norna fabric and is designed to wick away sweat and trap warmth. The structural weave offers maximum ventilation, which is further enhanced by the generous half zip. The gridded fabric provides best-in-class comfort and feels amazing worn next to the skin, with no itching at all. For the premium price, you get first-class manufacturing, such as triple-stitched flat-lock seams and bar tacking in stress points. If, like me, you are sensitive to wool being itchy, then this top will work for you. It has enough wool content to keep you warm and smell-free for days on end. The Huge Sweater is a full, all-season top and is one of the heavier options in the list (hence the sweater tag), so think late fall, into winter and early spring, rather than midsummer. Klättermusen are the master of refined, understated style in outdoor wear, and the Huge is no exception. The regular cut looks great both on and off the hill, and the high neck not only traps in warmth, but looks amazing with the offset zip. Finishing touches include trademark triangular inserts, embossed Klättermusen aluminium zip pull, discreet embossed logo and a lovely, elegantly hidden thumb loop in the deep wrist cuffs.
The Klättermusen Huge Half Zip Sweater comes in sizes XS-XXL and 5 colour choices for men and sizes XXS-XL and 4 colour choices for women.
The SRP is £160 and it can be purchased directly from Klättermusen UK or the London shop.
Rab Sonic LS Zip
This lightweight top ticks all the boxes for early season adventures. It’s well cut with a regular fit, which means that excess heat can be removed through the micro grid. More ventilation is provided by the generous half zip, which offers maximum opening, This can be zipped up to provide some warmth when the breeze gets up. Extra wind protection is provided by the reverse coil zip and high neck. The YKK zip is snapped into place with a spring lock which is a neat design feature. This top is super light, weighing in at just 130g it’s one of the lightest in the list, so it’s more of a three season top suitable for trail running, hiking and summer mountaineering, either on its own or under a lightweight outer such as a windproof shell. We really like the seam stitching on this top, which screams premium and feels great when wearing next to skin, it also has an order control treatment so you can wear it for long periods, confident that folk might still want to sit next you in the pub when you get down off the hill. Finishing touches include a printed logo and label, a hidden, internal thumb loop and a hanging loop for the drying room. The Rab Sonic LS Zip comes in a choice of 6 colours and sizes XS-XXL for men and UK 06 – 18 and 4 colours for women. All for the amazing price of £45, they can be bought direct from Rab UK and specialist retailers.
Helly Hansen LIFA Merino Midweight 1/2 Zip
Helly Hansen have been the OG of base layer tops for as long as I can remember. Many of you may have owned a LIFA “smelly helly” crew neck top with the iconic striped side sleeves. I have two in my own kit, and they have been faithful base layers for nearly 20 years—the LIFA Merino Midweight 1/2 Zip blasts away any smell in a puff of evaporated sweat. The 57/43 merino/polypropylene mix offers the best of both worlds: the durability, lightness and fast drying properties of a synthetic with the warmth, soft feel and odour management of merino. You can be confident that the top can be worn day after day without smelling and the regular fit offers maximum comfort. The 225g fabric offers warmth throughout all seasons and is probably best suited to late-season adventures, but you can be sure that with its unique, perforated synthetic inner and deep neck zip, it will work as hard as you do. Chaffing is eliminated with extensive flat seams and body-mapped cutting. Warmth can be trapped with the quality coil zip that is captured in a well-sized zip garage, and more warmth and comfort are added with the double-layer Merino neck, which is nice and high. I like the way this material works with the synthetic inners and merino outer, it feels less itchy (which I find merino can do on my skin). Finishing touches include a discreet HH logo on the neck and discrete signature stripes on the forearms.
The Helly Hansen LIFA Merino Midweight 1/2 Zip is available in sizes S-XXL and features an impressive 7 colour options. The female version comes in sizes XS-XL and 6 colour choices.
The SRP is £90 and it can be purchased directly from Helly Hansen UK and specialist retailers.
Jack Wolfskin Sky Thermal Half Zip
Another affordable option from German outdoor specialists Jack Wolfskin. This is more suitable for colder conditions than the Rab Sonic, with a nice soft feel and brushed fleece interior. Made from the tried-and-tested Texadri fabric, it wicks away sweat extremely fast, and the brushed inner means it feels great next to the skin. When it does get a little damp, the polyester dries out really quickly, so you can be sure to stay dry and comfortable, no matter how hard you are working. The regular fit allows for a more casual wear. Still, it’s not overly baggy, so it will easily fit under a fleece or lightweight rain jacket, providing a nice, lightweight system for fast and light adventures. The generous half zip features a reverse coil design to help keep out the chill, and the high neck also provides additional warmth. Don’t think affordable means cheap. Jack Wolfskin makes excellent kit, and you get plenty of the refinements of more expensive tops, such as flat-lock sewn seams, printed labels, double material on the neck, double-stitched cuffs and hems, and it’s Fair Wear, made to boot.
The Jack Wolfskin Sky Thermal Half Zip comes in sizes S-3XL for men with three colour options and XS-2XL with three colour options for women. The amazing price range from £40-45 is a bargain and they can be bought direct from Jack Wolfskin UK and specialist retailers.
Artilect Boulder 125 1/4 Zip
We featured an A/SYS-1 t shirt in our Speedhiking article earlier in the year and were impressed. It’s been performing brilliantly all through our hot summer for hiking and climbing. We have no hesitation in recommending the Boulder 125 1/4 Zip for the cooler months ahead. Made from Artilect’s proprietary, featherweight Nuyarn merino, it boasts the highest merino content in the list, offering 85% certified non-mulesed Australian wool and 15% Nylon, which enables the material to be both lighter and more durable than if it were 100% merino. This means the Boulder 1/4 Zip is nice and stretchy, as well as being super fast to dry. In fact, it wicks sweat away faster than you can say ‘wow, now that’s fast drying!’. Double-stitched flat lock seams, along with a body-mapped cut and a regular fit, provides a comfortable fit under any mid-layer. Ample ventilation is supplied by the generous, reverse-coil YKK zip, and we really like the perforated side panels, which is a neat design feature. The 125 gsm, light, weave also enhances ventilation, so much so that we would say this is more a three season top for wearing with a gilet and later season under mid layers and hardshell. The Artilect Boulder 1/4 Zip comes in at the premium end of the list and features several high-quality elements, including hidden thumb loops, flat-lock cuffs and hem, a lightweight hanging loop, a double-layered high neck with a great zip garage, and a generous placket to help keep the warmth in. Neat Artilect labels on the torso and arm finish it off nicely.
The Artilect Boulder 125 1/4 Zip comes in sizes XS-XXL and two colour options for men and sizes XS-XL and three colour options for women.
The SRP is £94.99 and it can be bought directly from Artilect UK and Ellis Brigham.
Disclosure – CGR reviewers and writers are never paid to provide a review and the website does not take advertising or link to affiliate sales. We are a bunch of keen climbers and travellers who accept sample products and offer an honest and independent review of the item.
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