Rukka ladies Lahti mid-layer jacket in black

The ladies Lahti may look like a down jacket, but it isn't quite that. The main body of the jacket is made up of a series of baffles, but those baffles don't contain genuine down; they contain a synthetic insulation made from a recycled fibres known as Repreve. This material has a resilient loft, it wicks moisture effectively, and it continues to work when wet. As an insulator, this filling basically does the same job as something like Thinsulate or Primaloft.

On the Lahti, the insulation is on the front and back of the jacket. There's nothing in the sleeves. And Rukka has done this on purpose, of course, partly because the main priority when it comes to staying warm on the bike is to protect the 'core'; but also because, by not have any insulation in the sleeves, the Lahti is going to be easier to wear under a motorcycle jacket.

The sleeves of the Lahti are constructed from a soft, stretch material. The jacket has a stand-up collar. There's a full-length zip up the front of the jacket. You also get two, zip-fastened, hand-warmer pockets. The side seams are also this stretchy material which is how they make this jacket fit ladies well.

So, as ever, there's no right answer; and no wrong answer. A proper down jacket with a high 'fill power' rating makes for an incredibly warm mid layer. But such jackets, even though they will squeeze down, come naturally with a degree of bulk. The Lahti will not be as insulating as such a jacket. It will, though, trap body heat, importantly it will wick sweat better than genuine down, it will fit more easily under a motorcycle jacket, and it will cost you a lot less.