Way too tight. I'm a medium in most brands and sometimes large but got the large in this and it's very snug. Kind of like a performance cycling fit - skin tight. Average warmth, good quality product but unless you are are long and slim shape bodytype then this is probably too tight.
I got 2 of these and also have a waterproof jacket with all itmes being on the very slim fit range. I could go a size up but the sleeves would be too long then. I'm keeping the items but focussing on losing weight!

Sizing not accurate between medium and large. Returned but 20 days later nothing and no response from Fjern contact us process. No contact number to call. Be warned !

I have owned one of these jackets for a year now. It’s the bright blue and yellow one and it’s a fab jacket for dog walking. I recommend this jacket . I have an under fleece too and that is warm and a great combination when walking in t(e North of England!

Bought a size up after checking their sizing on the website. Perfect athletic fit, nice and snug where it needs to be.

This is the second one I’ve bought and I’m still impressed with the fit (I’m broad shouldered) and the thermal qualities it has. Recommend.