Fastpack 20
Vest-harness day/fastpack (~23L) for long trail days and overnight kit — choose this when ADV Skin / Race Vest 6 run out of rear volume for layers, food and poles, not when you want a bounce-free race vest.
Available in Men's sizing.
- Fastpacking Packs
- Running Backpacks
- Best forFront access with real fastpacking volume as a weekly priority.
- CategoryRunning Packs & Vests
Overview
Vest-harness day/fastpack (~23L) for long trail days and overnight kit — choose this when ADV Skin / Race Vest 6 run out of rear volume for layers, food and poles, not when you want a bounce-free race vest.
A vest-harness ~23L UD Fastpack when ADV Skin / Race Vest 6 run out of kit space. Skip it for flask-only race days — women should start with FastpackHer 20.
- Vest-like front access with real pack volume for fastpacking and big trail days
- Reservoir sleeve plus front bottles cover long remote efforts
- Roll-top + side zip makes kit changes faster than a sealed race-vest rear
Kitletics Review · 8.8 Very Good
Ultimate Direction Fastpack 20 is a Vest-harness ~23L day/fastpack when race vests run out of kit space. I'd shortlist it for front access with real fastpacking volume. The trade-off is you only need a flask-only race vest. Skip it if you only need a flask-only race vest.
Read Kitletics Review →Performance scores
- Capacity9.2
- Bounce control8.6
- Race-kit capacity8.8
- Pole carry9.0
- Versatility8.8
- Weight7.2
Overall score: 8.8
Pros & cons
Pros
- Vest-like front access with real pack volume for fastpacking and big trail days
- Reservoir sleeve plus front bottles cover long remote efforts
- Roll-top + side zip makes kit changes faster than a sealed race-vest rear
Cons
- Heavier and warmer than a flask-only race vest for road/trail races
- Men’s Fastpack patterning — women should start with FastpackHer 20
How it fits different uses
| Use case | Score |
|---|---|
Fastpacking Top Fastpack pick for overnight and big-day trail kit. | 94 |
Trail Running Strong when training days need layers and poles beyond ADV Skin. | 86 |
Ultra Useful for ultra training volume; race days often stay on a vest. | 82 |
Long Runs Only when long runs need real rear volume and poles. | 78 |
Kitletics Review
A buying decision based on structured product data and evidence — not invented star ratings or fake user reviews.
Kitletics Review
Verdict
Ultimate Direction Fastpack 20 is a Vest-harness ~23L day/fastpack when race vests run out of kit space. I'd shortlist it for front access with real fastpacking volume. The trade-off is you only need a flask-only race vest. Skip it if you only need a flask-only race vest.
Pros
- Vest-like front access with pack volume
- Reservoir sleeve plus front bottles
- Roll-top kit access beats sealed race-vest rears
- Vest-like front access with real pack volume for fastpacking and big trail days
- Reservoir sleeve plus front bottles cover long remote efforts
Cons / Trade-offs
- Heavier/warmer than flask race vests
- Men’s patterning — women start with FastpackHer
- Heavier and warmer than a flask-only race vest for road/trail races
- Men’s Fastpack patterning — women should start with FastpackHer 20
Best for
- Front access with real fastpacking volume as a weekly priority.
- Roll-top + side zip makes kit changes faster than a sealed race-vest rear.
Not ideal for
- Those looking for only need a flask-only race vest.
- Those looking for Your fit, carry, or awareness needs sit outside what this product was built to do.
- Those looking for Heavier and warmer than a flask-only race vest for road/trail races.
- Those looking for Men’s Fastpack patterning.
Performance breakdown
- Role fit8.7· Editorial
- Value8.1· Editorial
Scale: Poor (1–3) · Fair (4–5) · Good (6–7) · Very Good (8) · Excellent (9–10)
How it performs
What it is
Vest-harness ~23L day/fastpack when race vests run out of kit space. Ultimate Direction Fastpack 20 is built for a defined role in the category — use that as your first filter. I'd shortlist it when you want front access with real fastpacking volume. Skip it if you only need a.…
Key specs
Here are the numbers that matter for the Ultimate Direction Fastpack 20: • Capacity: 23 L • Weight: 590 g • Bladder compatible: yes • Pole attachment: yes • Bounce control: high • Size range: S/M–M/L Treat specs as filters for capacity, fit, battery, waterproofing and.…
Where it is strongest
I'd buy the Ultimate Direction Fastpack 20 when these outcomes match what you need most weeks: What it does well • Vest-like front access with pack volume • Reservoir sleeve plus front bottles • Roll-top kit access beats sealed race-vest rears The standout is vest-like front.…
Trade-offs & limits
The Ultimate Direction Fastpack 20 is not trying to do every job. These are the compromises to weigh: • Heavier/warmer than flask race vests • Men’s patterning — women start with FastpackHer Skip it if: You need to avoid you only need a flask-only race vest. Those limits matter.…
Key specs that matter
| Spec | Value | Why it matters |
|---|---|---|
| Weight | 590 g | Affects how lively or protective the shoe feels on easy miles. |
Should you buy it?
Buy if
- You want front access with real fastpacking volume as a weekly priority.
- Most of your sessions line up with Vest-harness ~23L day/fastpack when race vests run out of kit space.
- Vest-like front access with real pack volume for fastpacking and big trail days
- Reservoir sleeve plus front bottles cover long remote efforts
Skip if
- You need to avoid you only need a flask-only race vest.
- Your fit, carry, or awareness needs sit outside what this product was built to do
- Heavier and warmer than a flask-only race vest for road/trail races
- Men’s Fastpack patterning — women should start with FastpackHer 20
Final verdict
Vest-harness ~23L day/fastpack when race vests run out of kit space. I'd shortlist it when you want front access with real fastpacking volume. Skip it if you only need a flask-only race vest.
Alternatives to consider
Ultimate DirectionRace Vest 6.0Why choose this instead: Classic UD front-pocket race layout for gels and flasks
8.9 · Very GoodFrom € 155Compare →
SalomonADV Skin 12Why choose this instead: Want better value?
9.0 · ExcellentFrom € 160Compare →
OspreyTalon Velocity 20Why choose this instead: Want better value?
8.6 · Very GoodFrom € 170Compare →
Compare with
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How we assessed it
We put this guide together from published specs and similar products in the same job. We have not personally tested this product unless the page says we did. Scores are meant to help you decide — affiliate links do not change the verdict.
Review type: Expert Research Review.
Read how we review products →Compare with
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Specifications
Specifications
| Capacity | 23 L |
|---|---|
| Weight | 590 g |
| Included Flasks | 0 |
| Flask Pockets | 2 |
| Reservoir Compatible | Yes |
| Reservoir Included | No |
| Bottle Capacity | 1000 ml |
| Bladder Compatible | Yes |
| Storage | Roll Top main with full Side zip access; front bottle/flask pockets; side and rear stretch stash |
| Front Storage | Twin front bottle/flask sleeves plus stretch harness pockets for phone, maps and fuel |
| Rear Storage | Roll Top ~23L main compartment with side zip panel access |
| Pockets | Front flasks, harness stash, side stretch, rear stretch, internal organization |
| Phone Storage | Yes |
| Pole Attachment | Yes |
| Quiver Compatible | Yes |
| Race-Required Gear Capacity | Yes |
| Helmet Carry | No |
| Compression Carry | Yes |
| Race Bib Features | No |
| Bounce Control | High |
| Breathability | High |
| Reflectivity | Yes |
| Whistle | Yes |
| Water Resistance | Water Resistant |
| Fit System | Infiknit / FastFlow vest harness with sliding sternum rails |
| Size Range | S/M–M/L |
| Sizing | S/M–M/L chest (verify current UD chart) |
| Fit / Sizing | Men |
| Race Suitability | Trail, Ultra, Adventure |
Fastpack family
Where to buy
Showing offers for Netherlands. Prices may change at the retailer.
Amazon.nl
in stockMarketplaceNLLast checked 12 September 2026€ 175View on Amazon
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Sources & evidence
Transparency behind this Kitletics Review — not a substitute for the buying decision above.
Editorial research
Independent expert reviews & Kitletics editorial analysis
Used to cross-check ride, fit, category placement and buying trade-offs. Not a Kitletics personal wear-test.
Verified 12 September 2026
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