Inov-8 Ultra Pack Pro 8 Review: A Comfortable 8L Hydration Vest With Surprising Storage

Introduction

Hydration vests have become a normal part of long-distance running, whether that is a big-city marathon, a long training run, or a full mountain ultramarathon. Inov-8’s latest entry, the Ultra Pack Pro 8, is an evolution of the award-winning Race Ultra Pro 5, and it keeps much of what made that vest so well regarded while adding a few genuinely useful upgrades.

After a month of testing, the new vest proved comfortable, stable, and impressively roomy for its stated eight-litre capacity. Here is a full breakdown of how it is built, how it performs, and what is worth checking before you buy.

Who This Vest Is For

The Ultra Pack Pro 8 is aimed at runners who need a proper carrying system for long runs and races: marathoners who want fluids and nutrition on the move, and ultra runners facing extensive mandatory kit lists. It retails in the UK for £140 and comes in three sizes (small, medium, and large) matched to chest measurements, in a single colourway of black with bright green detailing. High-visibility accents and logos on the front and back add safety for nighttime running.

Because it is a sized vest rather than an adjustable running pack, fit is more precise, which helps keep movement and bounce to a minimum.

Main Strengths

The bulk of the vest is a highly breathable, lightweight stretch mesh that contains recycled materials, giving a close, bounce-free fit with less risk of chafing, even when fully loaded. Inov-8 has clearly built on the previous model’s comfort record: over a month of testing there were no rubbing or irritation issues, and the vest stayed stable even when packed with kit.

Hydration is handled with two 500ml soft flasks included, and there are three ways to carry fluid. The traditional chest-mounted pockets are the best-performing option, freeing up two large side stash pockets. Alternatively, the flasks can sit in lower mesh pockets with long hoses routed through bungee cords, or a hydration bladder can be carried in the back via a velcro loop. Bungee clips over the flask caps stop the bottles slipping down into their pockets as you drink, a small touch that works very well.

Storage is where this vest genuinely stands out for its size. Up front there are two shoulder-strap stuff pockets (one holding a well-built emergency whistle), a left stuff pocket and a right secure zip pocket above the flask pockets, and two large stretchy mesh pockets at the bottom of the vest. Those side pockets wrap all the way around the back and join up, creating a 360-degree wraparound stash pocket similar in concept to the design used on the Salomon Advanced Skin 12. With decent shoulder mobility you can reach back and grab items on the move, making it an ideal spot for a waterproof jacket or trousers. Behind that sits the main rear compartment, a big stretchy pocket that swallows a full mandatory kit list in a dry bag.

Pole carrying is covered with two systems: substantial pole loops on the lower back, or a front-mounted bungee setup. Both held poles securely during testing.

Fit adjustment is flexible too. Beyond the standard strap-and-buckle cinch, the buckles can be repositioned at 13 different points along the adjustment system, and a bungee cord with a sternum strap inside the side mesh pockets pulls the vest in around the midriff for extra personalization.

Things to Consider Before Buying

A few trade-offs are worth knowing. The long hoses supplied with the flasks are fiddly to remove if you want to switch back to the standard short-straw setup; it took a good hour of fighting with them. The chest-mounted flask system is the better choice anyway, both for balance and because it is easier to monitor hydration and refill at race checkpoints.

One genuine step back from the previous version: the old Race Ultra Pro 5 had a velcro closure on the main rear compartment, while the new vest leaves that opening open. Nothing is likely to fall out, but some form of closure would offer more peace of mind. The bladder option also feels increasingly dated compared with chest-mounted bottles, which balance better, stay visible, and are simpler to refill.

Buying Advice

If you are upgrading from an older vest or choosing your first hydration system, the Ultra Pack Pro 8 is easy to recommend. For an eight-litre vest it carries like a ten to twelve litre pack, with enough volume for the mandatory kit lists of big mountain ultras such as UTMB or the Arc of Attrition. Breathability is noticeably improved over the previous model thanks to the ventilated mesh panels, and the fit is precise with very little movement even fully loaded.

If you prefer chest-mounted flasks, do yourself a favour and skip the long hoses from the start. And if you want a sealed main compartment, be aware this model does not have one.

Conclusion

The Inov-8 Ultra Pack Pro 8 refines an already successful design. Breathable recycled mesh, a clever 360-degree stash pocket, dual flask-carrying options, and two pole-carrying systems make it a very complete package for marathon training runs through to hundred-miler kit lists. Its main drawbacks, the fiddly hoses and the open main compartment, are minor against an otherwise comfortable, well-built, and impressively capacious vest.