When you’re picking an insulated jacket for big days out or multi-day hikes it’s worth considering warmth-to-weight ratios. You don’t want to be carrying a warm jacket that weighs a ridiculous amount when you’re putting in the miles, and conversely you don’t want something that weighs nothing but provides little warmth. You want something that sits halfway. And with its 350g (Size L) weight and 700 fill power down, that’s the Mountain Equipment Frostline

This is a down jacket that will have your back all-year-round. In winter, its medium-sized baffles allow it to fit comfortably underneath an outer layer like a hardshell, while it also should fit over any thick baselayers at the same time. Then in warmer months it’s that ideal option to pull out of your pack when the wind picks up or when you’re sat on a summit having your lunch.

There are lighter jackets with higher fill powers, but these usually come with a hefty price tag, and at the relatively fair price of £179.99, the Frostline is a decent compromise.

One of the drawbacks of down fill is the deterioration of its insulating performance when it gets wet. Once the feathers absorb water, they lose their loft and therefore the ability to trap warm air. These days however, brands are finding ways to get around this problem.

“A down jacket that will have your back all-year-round”

In the case of the Frostline Jacket, Mountain Equipment have used a durable water repellent (DWR) treatment that gives the down hydrophobic properties – a second defence behind the water resistant DriLite Loft outer fabric. Now, this doesn’t make the jacket waterproof but it does make it able to stand up to any light rain, wet branches or a tent floor that’s covered in condensation. And this is all without the use of the environmentally hazardous chemicals that are sometimes found in DWR coatings.