Trail running packs are all about balance: weight versus storage, breathability versus support, and minimalism versus utility. The INOV8 Ultrapac Pro 8 aims to strike that balance for runners who demand functionality across mixed terrain and weather conditions. Designed for fast mountain missions, ultramarathons, and everyday training, this 8-litre trail vest packs in hydration, nutrition, emergency gear, and layering — without weighing you down or bouncing you around.
With a claimed weight of just 345g (vest only), INOV8 markets the Pro 8 as a “premium-level trail running pack” that’s built to handle long distances. After logging more than 200km across the Peak District, Snowdonia, and the South Downs, we break down how it performs in real-world conditions.
Specifications at a Glance
| Feature | Details |
|---|---|
| Volume | 8 litres (plus stretch mesh expansion) |
| Hydration | Dual 500ml soft flasks + rear bladder sleeve |
| Weight | ~345g (vest only), ~430g with flasks |
| Fit | Unisex with six adjustment points |
| Pockets | 10+ including zip, mesh, rear stash, and pole |
| Materials | Ripstop nylon + stretch mesh panels |
| Extras | Pole storage, whistle, reflective detailing |
| Price (RRP) | £135 (discounted to ~£100 online) |
Fit and Comfort
Straight out of the box, the Ultrapac Pro 8 feels light, flexible, and remarkably stable. INOV8’s multi-point adjustment system allows you to fine-tune fit across the sternum, sides, and shoulders — making it suitable for a wide range of body shapes.
The slimline cut hugs the torso without squeezing or flapping, and the vest moves well with dynamic arm swings. On technical terrain and fast descents, it holds firm with minimal bounce, even when fully loaded with water, jacket, and gels.
The shoulder straps feature breathable mesh padding, which reduces sweat buildup and chafing during longer efforts. Dual sternum straps are height-adjustable and easy to tension — securing the front section while allowing chest expansion when breathing heavily.
Side cinch cords allow in-run adjustment and help tailor the fit for minimal movement over time, whether climbing, descending, or cruising along fire roads.
Storage and Organisation
Despite its minimalist silhouette, the Ultrapac Pro 8 punches well above its weight in pocket variety and internal organisation. Here’s a breakdown:
Front Pockets
- Dual flask pockets with elastic compression
- Zipped security pocket (left) for keys, ID, or cards
- Mesh dump pockets (right) for gels, bars, or gloves
- Whistle attachment under the chest strap
Rear Storage
- Large main compartment fits a lightweight jacket, emergency gear, or 1.5L hydration bladder
- Stretch mesh rear stash allows fast access to waterproofs or poles
- Zipped rear pocket ideal for valuables or phone (water-resistant lining)
- Pole loops secure collapsible running poles horizontally or vertically
Side Panels
- Expandable mesh sleeves store snacks, small bottles, or wind shells
- Compression toggles help cinch cargo down when partially loaded
Even with 8 litres nominal volume, the stretch fabric allows for impressive expansion. We packed a rain jacket, buff, gloves, phone, first aid kit, energy gels, and two flasks — with room to spare.
Hydration System
The vest includes two 500ml INOV8 Ultraflasks, which slide easily into dedicated chest pockets. These soft flasks feature extended drinking tubes, making it easier to sip without removing them.
Alternatively, you can fit a rear hydration bladder (sold separately) using the internal sleeve and hose port. We tested a 1.5L Platypus and found it compatible, though the hose routing is tighter than some higher-volume packs.
The ability to mix flask and bladder setups makes it adaptable for varied distances and water access. For ultra events, you can carry up to 2.5 litres with flasks and bladder combined.
On the Trail: Performance and Functionality
We tested the Ultrapac Pro 8 on runs ranging from 90-minute hill reps to 6-hour mountain traverses in mixed weather. Key performance highlights:
- Stability: Even when loaded with full hydration and gear, the pack remained snug and bounce-free
- Breathability: Mesh panels and moisture-wicking fabric kept our base layers dry and body temperature regulated
- Access: Front pockets were easy to reach during movement; rear stash worked well for layer changes at aid stations
- Pole storage: Secure and intuitive — though we preferred vertical carry over horizontal for less swinging
- Durability: After 200km, there was minimal wear on the seams, zippers, and mesh — no signs of stretching or stress
We especially liked how the rear stretch mesh allowed overstuffing — perfect for grabbing a waterproof or buff mid-run without breaking stride.
Comparisons: Ultrapac Pro 8 vs Similar Trail Vests
| Vest | Volume | Weight | Hydration | Price | Best Use Case |
|---|---|---|---|---|---|
| INOV8 Ultrapac Pro 8 | 8L | 345g | 2x flasks + bladder | £135 | All-day mountain runs, ultras |
| Salomon Adv Skin 5 Set | 5L | 300g | 2x flasks | £130 | Fast trail runs, short ultras |
| Montane Gecko VP+ | 8L | 330g | 2x flasks | £120 | Mountain running, fell races |
| Ultimate Direction Race Vesta 6 | 6L | 245g | 2x flasks | £125 | Lightweight races, short events |
The Ultrapac Pro 8 stands out with rear bladder compatibility and ample stretch storage. While slightly heavier than others, it adds versatility for longer outings and variable weather.
Durability and Long-Term Impressions
Over three months, including wet UK conditions and rocky descents:
- Zippers remained smooth, with no fraying cords
- Mesh held up against snagging brush and repeated stuffing
- Reflective strips stayed intact despite machine washing
The pack’s materials seem well chosen for long-term use without excess weight. It’s not a fast-race vest — but it thrives on endurance, mountain exposure, and multi-hour sessions.
Pros
- Lightweight yet stable at full capacity
- Excellent pocket variety and storage flexibility
- Breathable mesh for warm-weather runs
- Bladder compatibility adds hydration versatility
- Pole carry options are intuitive and firm
- Durable, low-profile construction
- Good value given technical features
Cons
- Slightly heavier than pure race vests
- No integrated rain cover or dry pouch
- Rear bladder hose routing could be improved
- Chest flask tubes may flop if not managed with clips
- Limited colour options
Final Verdict
The INOV8 Ultrapac Pro 8 offers a superb mix of storage, comfort, and on-the-move accessibility for serious trail runners. While not the absolute lightest in its class, it delivers the kind of reliability and modular functionality that mountain athletes, ultra competitors, and training-focused runners need.
Its ability to scale hydration systems, carry poles securely, and expand beyond its stated capacity makes it a trail vest built for adventure and utility. If you run long, run hard, and run remote — this is a pack that deserves consideration.
Rating: 9.2/10
Best For: Ultramarathons, mountain runs, all-day trail adventures
Avoid If: You want a featherweight race vest or minimalist setup
