Review: 66° North Grettir T-Shirt

A versatile base layer that’s lightweight and breathable with Polartec®’s new Fresh Face fabric technology

Feature type Review

Read time 4 mins

Published Aug 18, 2023

Author Josh Raper

Josh Raper Josh is a photographer and videographer specialising in capturing outdoor brands, travel and expeditions. Having been on expeditions around the world and supported adventurers & athletes on various challenges, he is a passionate outdoorsman and enjoys exploring new places.


Incredibly breathable and lightweight with Polartec®’s new Fresh Face technology, the 66 Degrees North Grettir T-shirt is a versatile base layer that is suited to a number of outdoor activities.  

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Features Polartec® Delta fabric with Fresh Face technology, lightweight Cool Mesh Jersey, Repairs for life warranty


  • Excellent odour control
  • Lightweight
  • Breathable


  • Comes up small
  • Only two colour options (if that bothers you)
  • Slightly on the expensive side for a t-shirt


Being an adventure and outdoor brand photographer and filmmaker, I tend to carry large, heavy rucksacks over questionable terrain, in all weathers. Therefore, I want a base layer I can rely on to be: A. comfortable, breathable and nicely fitting and B. have fantastic odour control so the people I’m working with don’t start avoiding me.

I’ve bought the classic, ‘cheap as chips’ base layers in the past along with some better quality ones from other well known brands, but these never seem to live up to their written credentials. They often start smelling within a few hours of use, and are quite bad at clinging to the skin when it soaks up moisture. Not to mention substantial heat loss once I’ve stopped moving and the wind chill kicks in.


Having first tried the Grettir T-shirt on at home and just milling around the house in the day, I was instantly impressed by how it felt and the fit – it didn’t really feel like I was wearing it! Compared to my other base layers, this felt particularly lightweight and I had a real sense of the freedom of movement it gives.

Compared to my other base layers, this felt particularly lightweight

Some people are put off by the texture of a mesh jersey fabric, but I personally didn’t have any problems with it and it just enhances the nice feeling of it being well-fitted. One thing I would say is that the size does come up a bit small so be aware when selecting your size. It does have a habit of riding up – not great if you’re wearing a rucksack or cycling for example.


Now the weather seems to finally be improving, and wanting to give the Grettir a proper trial, I took it out for a test-drive both running and hiking. Being based in Bristol and only a 25 minute drive to Black Down, the highest point of the Mendips at 325m above sea level, I disappeared into the hills to see how it would perform.

With temperatures hovering around the low-mid twenties and a clear sky at midday, I could certainly feel the heat coming off the hillside. Making my way around this part of the mendips with a reasonably loaded pack, I could feel my arms, legs and head begin to sweat, but amazingly the parts of my body that were covered by the Grettir T-shirt didn’t feel at all sweaty or clammy. Likewise, Once I was past the trig point and up on the ridgeline, I felt well protected from the potential wind chill and wet cling (when a fabric gets so saturated with moisture that it sticks to the body). It certainly isn’t windproof (and you wouldn’t want it to be) but it was very good at keeping my body temperature regular throughout being active and stationary, without the need to constantly swap and change my layering system. 

Now, what I really wanted to put to the test was its claim of ‘excellent odour resistance’. Every brand under the sun deems their base layer products to be odour resistant, or even stopping odour from even occurring, and from my experience and others I have spoken to, these products often fall short of the mark. The Grettir T-shirt is made using Polartec® Delta fabric, and this year the brand introduced a new odour-reducing technology to replace their previous silver-based additive. Fresh Face is derived from a naturally sourced and non-GMO mint plant, and promises to deliver the same standard of odour control as silver, but it production methods are significantly kinder to the environment. 

I wanted to test this minty new tech as thoroughly as possible, so, I didn’t wash it during 2 hikes and 1 run across 3 separate days! I was pleasantly surprised at how well it actually lived up to its claim of odour resistance, much better than I anticipated in all honesty. Now, I won’t sit here and claim it didn’t smell, because after the third day it was beginning to whiff a little bit, but after 2 full days in the hills and a run around my local area, I’d say that’s pretty good going. I certainly reckon I could have gotten away with a fourth day before I would begin to consider why people were not standing too close to me.


The Grettir T-shirt would suit anyone looking to be active in the great outdoors in most seasons (or even at the gym) and those who want a ‘do it all’ base layer.



The tight fit along with the high cut on the sleeve allows you to move in it however you want, whether you’re running, cycling, hiking or just about any other activity in the outdoors.


This base layer disperses moisture vapour away from the body rather than soaking into the fabric, reducing any clinging to the skin. Then, the new Fresh Face element works to massively reduce odour emitting from the product. 


The Polartec® Delta specialised knit construction uses both hydrophobic and hydrophilic yarns for more advanced control of moisture dispersal. The way this fabric knit is structured keeps you cooler in hot conditions by increasing airflow to dissipate heat, but also reduces the effects of wind chill and sweat soaked material which could result in a rapid drop in body temperature 


It’s really hard to tell you’re wearing anything being so lightweight. Also packs down super small so very easy to pack.

the new Fresh Face element works to massively reduce odour emitting from the product


£50.00 may seem like a reasonably high price for a short-sleeved base layer, but the value for money is arguably unmatched by its competitors. The combined technical features along with the perfect fitting gives the result of a garment that is multi-functional and can be worn for multiple days without needing to worry about getting smelly armpits and losing friends. Having worked in the outdoor retail industry in the past, I can tell the build quality of the Grettir is made to last.


At nearly 100 years old and based in Iceland, the literal land of ice and fire, 66° Degrees North are the experts in producing outdoor gear that stands up to brutal conditions, and the Grettir T-shirt is no different. Apart from the snug fit and being at the upper end of the price scale, it’s hard to find much to complain about in terms of performance, having used it during various degrees of strenuous activity. If you’re looking for a short sleeved base layer that you could use for pretty much anything, for a few days at a time, then this is a winner.

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