When looking for a down jacket, you will often see the number "800FP" on product pages. While a higher number may look warmer, some 800FP jackets are thin and lightweight, while others are plump and thick.
To understand the difference, consider how much the down puffs up, how much down is inside, and how the jacket is made. Looking at these three factors in order will make it easier to choose the right jacket for the occasion.
800FP is a measure of how well down puffs up
FP stands for "Fill Power." It represents the volume that 1 ounce of down puffs up under certain conditions. 800FP means that 1 ounce of down puffs up to a volume of approximately 800 cubic inches.
Down traps air in the spaces created when it puffs up. This layer of air makes it harder for body heat to escape. High-fill-power down puffs up more even at the same weight, so it is also used in jackets where lightness is a priority.
Is 800FP warmer than 700FP?
Here, you should also look at the actual amount of down inside the jacket. In the product specifications, this may be listed as "down fill weight" or "fill amount" and may be displayed in grams.
For example, a 700FP jacket with plenty of down may be warmer than a lightweight 800FP jacket. Differences in construction, such as how easily wind can enter through the cuffs or hem, and whether it covers up to the neck, also affect how warm it feels when worn.
| Item | What does it represent? | How to evaluate it |
|---|---|---|
| Fill Power (FP) | The volume that a certain weight of down puffs up | Use as a reference when lightness is a priority |
| Down Fill Weight (g) | The weight of the down inside the jacket | Look at it along with the fill power and jacket construction |
| Product Weight (g) | The total weight of the jacket, including the fabric and zipper | Use as a reference when carrying it for long periods |
Commuting, traveling, hiking. Think about the occasion
For commuting or walking around town, look at how easy it is to layer
Even if it is chilly outdoors in the morning and evening, it can feel warm on trains or inside stores. When looking for a jacket you will wear often, check whether there is enough room around the shoulders and arms to layer over your usual sweaters or sweatshirts.
If you will be exposed to the wind for a long time on station platforms, you should also check the construction of the neck and cuffs.
For travel, also consider the time you will not be wearing it
At a destination where it is warm during the day and chilly only in the morning and evening, you may spend surprisingly long periods carrying your down jacket. If you want to keep your luggage light, it is useful to check the product weight and the size when stored. Imagine the coldest situation you will face while traveling, such as when leaving your accommodation for dinner or waiting outdoors, and choose accordingly.
For hiking, think about walking and resting separately
Even if your body warms up while climbing, you may suddenly feel chilly when you take a break. By adjusting your temperature with a fleece while walking and putting on the down jacket during breaks, you can more easily regulate your body temperature according to the situation. On days when wind or rain is a concern, also check whether you can layer a shell over it.
Monterest 800FP Down Jackets
Monterest offers the 800FP Hooded Down Jacket (26NOYR002) and the 800FP Knit-Trimmed Hooded Down Jacket (26NOYR003). On the product pages, also compare the shapes of the hood and cuffs, as well as the silhouette in the photos. Imagining how to layer it over your usual clothes will help you find the right jacket for you.
800FP is one clue to understanding the characteristics of down. If you are unsure, first imagine when and where you want to wear it. Then, by looking at the fill weight, length, and ease of layering, you will see differences that numbers alone cannot reveal.
