On an ultra, your waterproof jacket spends 90% of the time rolled up at the bottom of your pack, and the other 10% it decides your race. Raidlight, the French brand born in the Chartreuse massif, knows this paradox better than anyone. With the Top Extreme Ultra MP+ 20K/20K, it promises mountain-grade protection, a featherweight build and a clever detail few rivals offer: a back gusset that lets you run with your pack underneath. We put it through rain, wind and long hours under a race pack.
The Raidlight Top Extreme Ultra MP+ is a 20K/20K waterproof, breathable trail jacket, certified for ultra mandatory gear, that weighs about 225 g and costs 159 euros. What sets it apart is a back gusset that lets you pull it on over a hydration pack of up to 18 liters, without stretching it out of shape or losing waterproofing. It targets trail runners who want real long-lasting protection without blowing their budget on premium brands.
8.5 / 10 · RunMorph overall score
While the big outdoor brands push premium membranes at 250 euros, Raidlight has spent years working a precise niche: gear designed by and for ultra trail runners, at an accessible price. The Top Extreme Ultra MP+ sums up that philosophy. Its in-house MP+ membrane is rated 20,000 Schmerber for waterproofing and 20,000 g/m2/24h for breathability. That is the level you expect from a real mountain jacket, not from a water-repellent windbreaker that gives up after twenty minutes of downpour.
At RunMorph, we see that this is exactly where the difference is made on an ultra. A jacket sold as waterproof but limited to 10,000 Schmerber wets out as soon as the rain settles in and the pack rubs against your shoulders. 20K/20K changes the game on long exposures. This Raidlight plays in the same league as the Salomon Bonatti Trail, with one argument the Salomon doesn't have: the back gusset.
| Brand | Raidlight (French brand, Chartreuse) |
|---|---|
| Model | Top Extreme Ultra MP+ 20K/20K (2025) |
| Type | Waterproof trail / ultra jacket |
| Membrane | MP+ 2.5-layer, heat-sealed seams |
| Waterproofing | 20,000 Schmerber |
| Breathability | 20,000 g/m2/24h |
| Claimed weight | about 225 g |
| Signature feature | Back gusset for packs up to 18 L |
| Hood | Adjustable, fits over a cap |
| Certification | Meets ultra trail mandatory gear requirements |
| Eco-design | Recycled fabric, PFC-free DWR |
| Official price | €159 |
The number that sums up this jacket is that double 20K. At this level, you no longer wonder whether the rain will eventually get through: the question becomes managing sweat, and that is where high breathability really earns its keep on long efforts.
Most waterproof jackets are worn under the pack. The result: when it starts raining mid-race, you have to take off your hydration vest, put on the jacket, then put the pack back on over it, all in a downpour with numb fingers. The Top Extreme Ultra MP+ flips that logic with a stretch panel in the back that opens up to wrap around a pack of up to 18 liters. Your gear stays in place and you pull the jacket on over it in a few seconds.
In use, the idea holds up. The gusset stops the jacket from being stretched to bursting point over the pack, removes the friction point that always ends up letting water in, and keeps your soft flasks within reach. It's the kind of detail you never notice in the store and that becomes priceless in the thirtieth hour of a race.
We took the Top Extreme Ultra MP+ on long runs of 2 to 6 hours, in steady rain and gusty wind, with a loaded 10 L vest. First finding: the waterproofing holds. Even after an hour of sustained rain, the inside stays dry, including at the shoulders where the pack presses down, which is often the Achilles' heel of race rain jackets. The fitted hood adjusts with one hand and doesn't block your peripheral vision.
On breathability, the 20K does the job at endurance paces, around 6 to 7 min/km. Condensation stays under control as long as you don't push hard. Like any membrane, though, it hits its limits when the intensity climbs sharply on a long ascent: that's when you need to work the zip to vent. Folded, the jacket packs into its own volume down to the size of a small grapefruit, easy to slip into a front vest pocket.
RunMorph's advice. A rain jacket is useless if you leave it dry at home because it's too bulky. The right reflex is to choose a jacket compact enough to live permanently in your pack, and protective enough for real conditions. The Top Extreme Ultra MP+ ticks both boxes. For your lower body, pair it with a good pair of technical shorts such as the Salomon S/Lab Ultra 2in1, and with a suitable pack like the Raidlight Ultralight 12L.
| Criterion | Raidlight Top Extreme Ultra MP+ | Salomon Bonatti Trail |
|---|---|---|
| Waterproofing | 20,000 Schmerber | 20,000 Schmerber |
| Weight | about 225 g | about 195 g |
| Pack gusset | Yes (up to 18 L) | No |
| Price | €159 | higher |
| Strength | Ultra versatility and over-the-pack fit | Lightness and low profile |
The comparison doesn't crown an outright winner. The Salomon Bonatti Trail remains the benchmark for lightness and low profile if you want the bare minimum in your pack. The Raidlight, slightly heavier, wins on real-world versatility in long races thanks to its gusset, and on a gentler price for protection that is identical on paper.
The Top Extreme Ultra MP+ is aimed first at trail runners who line up for races where a waterproof jacket is on the mandatory gear list, and who want reliable protection over several hours without going broke. It will also appeal to fast hikers and mountain runners who like keeping their pack in place. Road runners looking for a 100 g windbreaker for cool mornings should turn to a more minimalist model: this is real weather protection, not a simple wind shell.
A jacket will never get you to the finish of an ultra. Your training will. Gear keeps you safe, but preparation is what gets you to the line. To build your endurance, handle elevation gain and show up ready for your next long trail race, structure your weeks with a suitable plan. Check out the RunMorph training plans and turn your runs into real progress.
The Raidlight Top Extreme Ultra MP+ is a pragmatic success. It doesn't try to be the lightest or the trendiest. It goes for raw effectiveness in ultra: 20K/20K protection that lasts, a genuinely useful gusset and a price that stays below the symbolic threshold of the premium brands. Its only real drawbacks, a decent rather than record-breaking weight and breathability that tops out at high intensity, come with every membrane at this level. For French trail runners who want reliable, clever gear without overpaying, it's one of the best choices right now. RunMorph score: 8.5/10.