Comparison
Same trail-carry conversation, different jobs. Fastpack 20 is a vest-harness ~23 L pack for overnight kit and big trail days; ADV Skin 12 is a race vest for bounce-free flasks and mandatory race volume.
Ultimate Direction
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.
From € 175
Salomon
12L race vest for trail and ultra hydration.
From € 160
When each shoe is the better buy — by training mix and conditions, not overall score alone.
Bottom line
Choose Fastpack 20 when rear volume for layers, food and overnight kit beats race-vest bounce control. Choose ADV Skin 12 for race days and training where soft-flask front access and low bulk matter more than pack capacity.
Ultimate Direction
Choose Fastpack 20 if…
Salomon
Choose ADV Skin 12 if…
Fastpack beats ADV Skin when capacity is the constraint; ADV Skin wins when bounce-free race carry is the constraint.
Context winners by session type — use these with the decision guide above, not as a universal ranking.
Long Runs
ADV Skin 12
Long runs rarely need Fastpack rear volume.
Fastpacking
Fastpack 20
Overnight and big-day volume Fastpack wins.
Trail Running
ADV Skin 12
Most trail training days fit ADV Skin better than a fastpack.
Ultra
ADV Skin 12
Race-vest bounce and flask access for ultra race days.
VSValue
TIE
Kitletics value scores are too close to call on current catalog pricing.
| Spec | Fastpack 20 | ADV Skin 12 | Winner |
|---|---|---|---|
| Capacity (L) | 23 | 12 | — |
| Total Hydration Capacity (ml) | — | 2500 | — |
| Weight (g) | 590 | 270 | ADV Skin 12 |
| Fit / Sizing | Men | Unisex | — |
| Bounce Control | High | High | TIE |
| Race-Required Gear Capacity | Yes | Yes | TIE |
| Race Suitability | Trail, Ultra, Adventure | Trail, Ultra | — |
| Included Flasks | 0 | 2 | — |
| Included Flask Volume (ml) | — | 500 | — |
| Bottle Capacity (ml) | 1000 | 1000 | TIE |
| Flask Pockets | 2 | 2 | TIE |
| Bladder Compatible | Yes | Yes | TIE |
| Reservoir Compatible | Yes | Yes | TIE |
| Reservoir Included | No | No | TIE |
| Phone Storage | Yes | Yes | TIE |
| Pole Attachment | Yes | Yes | TIE |
| Breathability | High | High | TIE |
| Quiver Compatible | Yes | Yes | TIE |
| Sizing | S/M–M/L chest (verify current UD chart) | XS–XL (verify current chart) | — |
| Size Range | S/M–M/L | XS–XL | — |
| Fit System | Infiknit / FastFlow vest harness with sliding sternum rails | SensiFit + Quicklink | — |
| Storage | Roll Top main with full Side zip access; front bottle/flask pockets; side and rear stretch stash | Multiple front and rear pockets for flasks, gels and mandatory kit | — |
| Front Storage | Twin front bottle/flask sleeves plus stretch harness pockets for phone, maps and fuel | Twin soft Flask pockets + stretch snack pockets | — |
| Compression Carry | Yes | — | — |
| Rear Storage | Roll Top ~23L main compartment with side zip panel access | Main zip + stretch rear stash | — |
| Pockets | Front flasks, harness stash, side stretch, rear stretch, internal organization | Front flask/gel, rear main, side stash | — |
| Race Bib Features | No | — | — |
| Helmet Carry | No | — | — |
| Water Resistance | Water Resistant | None | — |
| Reflectivity | Yes | No | — |
| Whistle | Yes | Yes | TIE |
Regional prices · Netherlands
Prices last checked: 12 Sept 2026. Offer updates do not mean the editorial comparison was re-reviewed.
Ultimate Direction FastpackHer 20a similar peer is the fork: FastpackHer 20 (Women’s-specific Fastpack 20 sibling — same ~23L fastpacking role (overnight kit, layers,…) versus Fastpack 20 (Vest-harness day/fastpack (~23L) for long trail days and overnight kit — choose this when…). Source verdict cue: A vest-harness ~23L UD Fastpack when ADV Skin / Race Vest 6 run out of kit space. Skip it for flask… Spec split — peer weight 580 vs source weight 590.
Osprey Duro 15Duro 15 is on the Fastpack 20 alternatives list for a same-role peer. Duro 15 brief: Men’s 15L run-hike Osprey with Hydraulics reservoir support — for long trail days, advent…. Fastpack 20 brief: Vest-harness day/fastpack (~23L) for long trail days and overnight kit — choose this when…. Extra peer cue: hydraulics ecosystem matches Osprey hiking kits. Peer spec: weight 490.
Black Diamond Distance 15Distance 15 is on the Fastpack 20 alternatives list for a same-role peer. Distance 15 brief: 15L alpine running backpack (not the Distance 8 race vest) — vest harness with real pack…. Fastpack 20 brief: Vest-harness day/fastpack (~23L) for long trail days and overnight kit — choose this when…. Extra peer cue: built-in Z-pole sleeves beat dangling race-vest pole loops on alpine terrain. Peer spec: weight 330.
Osprey Talon Velocity 20Pick Talon Velocity 20 over Fastpack 20 only if osprey fit system dials torso length better than most race vests is the weekly gap. Talon Velocity 20 is fastpacking / trail training; Fastpack 20 stays fastpacking / trail training. Cost of the switch: heavier empty than UD Fastpack 20 or BD Distance 15.
Ultimate Direction Fastpack 30Fastpack 30 is on the Fastpack 20 alternatives list for a same-role peer. Fastpack 30 brief: 30L Fastpack for multi-day fastpacking and heavy mandatory-kit ultras — pick it when Fast…. Fastpack 20 brief: Vest-harness day/fastpack (~23L) for long trail days and overnight kit — choose this when…. Extra peer cue: reservoir + bottles scale hydration for remote multi-day routes. Peer spec: weight 700.
Ultimate Direction Race Vest 6.0Fastpack 20 vs Race Vest 6.0 is not a score swap. Race Vest 6.0 wins when a lighter option and classic UD front-pocket race layout for gels and flasks beat vest-like front access with real pack volume for fastpacking and big trail days. weight sits lower on Race Vest 6.0 (215 vs 590).
Salomon ADV Skin 5Shared use-case alternativeWe don't sell gear. Guidance is independent, labelled honestly, and evidence-led.
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