Description
Recommended Use:
The Mountain Racer is ideal for trail runners and mountain athletes who need a high-capacity waist pack without compromising performance. Perfect for long training runs, mountain races, or fast missions where you want to stay agile while carrying hydration, nutrition, poles, and essential gear. Built for rugged environments and multi-hour efforts where durability, access, and comfort are key.
Details:
• High-capacity 3L waist pack designed for rugged mountain and long-distance trail use
• Premium materials offer enhanced durability and weather resistance
• Large kangaroo-style front pocket with inner phone sleeve and layered zippered storage
• Two large side pockets with compression straps and cord locks for secure gear storage
• Rear pocket securely holds included 800 mL softflask with new locking cap
• Light bracket compatible for waist-mounted lighting solutions
• Removable rear Z-pole attachments for customizable loadout
• Ergonomic design ensures stable fit and minimal bounce during high-output movement
• Soft, breathable materials for long-wear comfort
• Available in three sizes: Small (28–32″), Medium (31–34″), Large (33–37″)
Fit: Unisex
Size: Sized- Small (28–32″), Medium (31–34″), Large (33–37″)
Color options: Steel Gray
Hydration (Included)- 1x 800 mL Softflask with Locking Cap
Does Not Include: Light Bracket
Capacity: 183 c.i. (3L)
Weight: 4.8 oz (136 g)
David (verified owner) –
Amazing! It’s incredible how much stuff fits in here! I’ve worn this on several runs since getting it this week and everything I need to carry finds a perfect spot on the belt. Everything stays tight without causing pressure points. I’m not sure how they made a fabric this stretchy while still holding things tight. The details are thoughtfully designed and just make so much practical sense. No chafing and the adjustable tightening straps work make for a perfect fit. Love this! I may never wear my vest again for anything sub-ultra.
I’m excited to buy the light attachment as the days are getting shorter and I’ll be running in the dark more.
Great product!
Dandelion –
I have always been a vest person and never really liked the feeling of anything on my hips while running. However, there is something about the cut of Mountain Racer that makes it couture so perfectly to my body that I hardly feel it! Though low profile, this well thought out and spacious belt can carry all the essentials needed for light and fast alpine missions. There is room for my nutrition, keys, layers, poles, hydration, phone, illumination and poles! Plus, the materials are highly durable so I don’t need to worry about gear failure in the unforgiving high mountains. Hugely innovative piece of technical equipment that I highly recommend for mountain runners and adventurers
Tanner W –
I am going to be honest here, this is the best running belt out there, by far. It is SO stable, comfortable and easy to use. I can easily pack over a liter of water on me, gels, headlamp, toilet paper, extra lube, keys, and still have room to spare, like a lot of room. Not to mention all with no bounce! It’s incredible. Seriously, if you have been in the market for a highly durable, high capacity, ultra comfortable running belt, there is no question this is the one! Thank you Ultraspire for yet another incredible product!
Brad (verified owner) –
It took me about 5 runs to get this belt dialed in but it’s became my go to when running. I am usually a size 32-33 waist, and I needed to size up to the large for it truly to work well for me.
The front slide in pocket fits the skinny flasks perfectly, but anything larger than those caused my waist belt light to fall out or the flask itself to fall out.
I like this belt especially for bigger days. When combined with tights that have side pockets, I could fit the required gear for Tushars 100k (think: rain jacket, emergency blanket, whistle, and light) plus two flasks and nutrition WITHOUT the need to wear a vest. The built in ability to use a waist lamp makes it great for overnight 100 milers.
If you don’t like running with a vest but need to carry more stuff, this is the belt for you.
Grant (verified owner) –
This is THE best belt on the market; why aren’t there more reviews on this? There is another belt out there getting all the reviews these days but I think the UltrAspire Mountain Racer is the one to get. First, its cheaper. Second it has pockets that enable better organization of stuff. It has great pockets for phones, keys and other stuff. There is zero bounce. The only downside is that the adjustment straps are over the side pockets which makes it hard to access them on the move but its a minor issue at best. I don’t think I will use my vests anymore unless I am doing something long and unsupported.
Brittany (verified owner) –
Fits well, tons of space, doesnt bounce, poles fit great. Game changer awesome addition for longer efforts/multi day events and great standalone for short days!
Courtney C –
Very comfortable and minimal bounce. I like to wear it closer to the hips than the true waist. Sizing is a little challenging (I wear women’s 6-8 in pants and the medium is perfect). I have used it with the 850 Duo waist light in combination with the Zygos for an all-night unsupported run.
Jess Riffner –
I’m completely sold on the Ultraspire Mountain Racer Waist Pack. Hands down, it’s the best waist pack I’ve ever used (and I’ve tried a lot). I find myself reaching for it almost every time I head out to the trails, leaving my vests on the shelf.
The fit is spot-on (I wear a size Small with a 28″ waist), and there’s zero bounce, even when it’s fully loaded. That alone makes it a standout. But Ultraspire didn’t stop there. The addition of the Lumen Light Bracket is a game-changer for pre-dawn runs. It keeps your light perfectly positioned without any fuss.
Every pocket on this pack is well thought out and genuinely useful. No wasted space, no awkward access points. It feels like every design detail was tested by real runners who get it.
No complaints. None. Ultraspire nailed it with this one.
Nam (verified owner) –
The best belt/waist pack I’ve used. I just used this for the first time on a 20 mile run and had zero issues. No bounce, no chafing, nothing lost. The volume is fantastic and all pockets are easily accessible while running. Note that the side pockets now have an improved design from the ones shown in the photos (writing as of late October 2025) so the tightening straps don’t cover the pockets.
The front pocket organization is well thought out and isn’t just a huge pocket where things get jumbled up. There are three layers which allow separating items like food, valuables, and trash.
I can fit the 800 ml bottle along with gloves and other items (like my phone) in the back pocket without discomfort and can still easily access them. This is a game changer and quite difficult to do with other belts on the market. The pole storage is great. The adjustable bungees allow accessing the back pocket items easily compared to belts that have static pole bungees. Additionally, I love that the back pocket has side pass through holes which allow you to run a hydration hose from the back bottle to the front. That feature is missing on other belts.
I’m a size 5 Naked band and the small of this fits perfectly. I don’t need to tighten it at all.
Renee Hoffmann (verified owner) –
The thing is the best!
I initially saw an interview with a runner who did Mammoth saying he used this belt, which piqued my interest. Then I did some Reddit research and determined I wanted this belt over the competitor’s option. I’ve taken it on a couple short-ish runs so far and love it. I plan to use this belt for my upcoming races (50k, 50-miler, and 100-miler) rather than a vest to help me stay cooler and keep the strain off my shoulders. It can easily hold more than enough water and fuel plus integrates with the UltraAspire lights I already have.
Adriano Alcoz (verified owner) –
Great Belt! This belt stays in place (i .e. doesn’t ride up), doesn’t bounce, and has a ton of storage. The included 800 ml flask fits perfectly into its pocket and is easy to stuff back in. I’ve tried numerous other belts & vests and this is head and shoulders above anything I’ve tried.
Matt B (verified owner) –
There should be more reviews for the mtn racer, this is the best trail running waist belt I have tried! Fits very secure and you can load it up with a surprising amount of things. The belt has a little stretch so it’s easy to get on/off, but while running I forgot I was wearing it! It doesn’t interfere with my vest so I can still wear both if needed but honestly I think just the belt will work for the majority of my runs.
I’m 5’11” 145lbs and the medium fits great.
Lindsey Duffield (verified owner) –
I have worn this on numerous hot and humid 50k-ish adventures! I love the way it packs 1 liter of hydration, plus all my fueling needs!
Nicole Laughton –
My Go To! Honestly, it’s hard NOT to grab this for 90% of my runs. The freedom of free hands, the large capacity for 800mL, and all the pockets help me carry and organize everything I’ll need. My system is: Gels in front outer pocket, phone in front zipped pocket, salt tabs in R pocket, trash in L pocket, and it’s just so easy to have everything, the great waist light for dark runs, and the snug fit means no bouncing or twisting.
tanner.swift (verified owner) –
This thing is amazing. You can fit everything you need in it. I like the front storage options that work great. The two side pockets are great for gels and other various items. I used the back pouch with the 1 liter soft flask which works in M/L sizes. I bought the blottle attachment with a mag clip and ran around front so I could drink without having to take bottle out which was great. On the front I ran the lumen clip with the 850 duo light during the night and it did not bounce around at all. This is the only belt I will wear going forward and highly recommend.
Deanice Shegog (verified owner) –
I ordered this belt as a hopeful replacement for my vest. It is difficult for me to find things that do not irritate my body. I must say I was skeptical about this belt and was worried about the fact that I needed to wear it before I could determine if it would work for me. Which means, I would be stuck with another piece of pricey equipment that I couldn’t use (I can’t even count how much I have in my closet that I can’t use and can’t return). However, I was pleasantly surprised at how well this belt fit. I am 5’4 and 110 pounds. I ordered the small and it fit great. I am short in my torso but the belt landed perfectly between my last rib and hip bones. I have had 21 bilateral hernia repairs and the meshing is a hot mess and easily irritated. I wore the belt on an 18 mile run with no pain or discomfort. The movement of the belt was minimal. It is comfortable and has plenty of storage. I can say good bye to tight shoulders and breast bruising from water bottles!
I took one star off because I will not be able to wear it in the summer heat. It is simply too warm. It has to have a shirt underneath to prevent chaffing as well. It will be perfect for my fall and winter races though.