Atom Packs Atom+ 40L Review

Overview

The Atom+ is a beefed-up version of Atom Packs’ original frameless Atom, built on the same body but with an increased torso length to accommodate a removable hip belt and a foam back panel housing a removable carbon hooped frame.

Atom Packs is a cottage gear company based in the Lake District, founded by Triple Crowner Tom Gale — a professional mountain leader with over 12,000 miles under his feet.

The result is a pack that threads a real needle: ultralight enough to keep your base weight honest, structured enough to actually carry a week’s worth of food without turning into a sack of suffering. Worth noting:

the Atom+ was later renamed the Pulse, with reviews updated to reflect the new name as of August 2024.

If you’re shopping the current lineup, you’ll find it listed as the Pulse — same DNA, new badge.

Key Specs

Spec	Detail
Weight	640g (22.6 oz)
Volume	40L main + front stretch pocket
Load Capacity	13.5 kg / 30 lbs
Torso Range	15”–23”
Hip Belt Range	30”–38”
Frame	Removable carbon fibre hoop
Main Fabric Options	VX21, VX07, LS21, 210D Robic Extreema
High-Wear Fabrics	Robic Extreema (shoulder straps, side pockets, hip belt), Bullet Mesh, Spacer Mesh
Closure	Roll-top with snap buttons
Pockets	2 side, front stretch, bottom (with trash port), shoulder strap pockets
Origin	Handmade in Keswick, Lake District, UK
Comparison	See how Atom Packs Atom+ compares to similar gear

Performance

Carry & Suspension

The carbon fibre hoop is the defining feature of the Atom+ and, frankly, what separates it from the crowd of sub-700g frameless packs. By utilizing carbon fiber’s exceptional stiffness-to-weight ratio, the frame provides the structural tension necessary to prevent the pack fabric from collapsing under the weight of a heavy resupply, and shifts the load from the shoulder straps down into the padded hip belt. In practice, the hooped frame keeps the back panel flat and flush against the spine, maintaining a narrow and tall profile that helps you feel more agile on technical terrain — and even during high-volume desert hauls with extra water, it remains rigid enough to prevent the pack from sagging.

That said, there are real limits. The pack is most comfortable when kept under its maximum load capacity; it gets a little uncomfortable around 25 pounds, as the minimalist carbon hoop frame and semi-narrow hip belt won’t transfer weight to the hips as well as some other packs. It also lacks load lifters that could shift weight closer to the body. If your base weight is north of 20 lbs before food and water, this probably isn’t the right tool. But used as intended — a refined UL kit under 25 lbs — the Atom+ is exceptionally comfortable; just don’t consistently carry loads over 30 pounds, and it’ll be more comfortable than most ultralight packs.

The removable hip belt is a genuine asset for versatility. With the hip belt removed, the pack drops to about 1.2 lbs / 550g — useful for day hikes or weekenders — yet with it attached it’s good to carry 30+ pounds comfortably on a thru-hike. One practical note: getting the hip belt on and off can be a challenge; sliding a piece of cardboard between the hip belt and the pack makes it much easier to remove and also helps you position it correctly when putting it back on. A few users on Trailspace and The Trek’s comments echo this — it’s a minor but real friction point on the trail.

Shoulder Straps & Comfort

The S-shaped shoulder straps are made of 3D mesh and 10mm foam, with the mesh allowing air to flow between the straps and your body. The S-shaped curve makes the pack very comfortable.

Even during long days of 8+ hours of hiking, one reviewer reported no chafing — even when using the pack without the hip belt.

Fit sensitivity is worth flagging: comfort and usability depend heavily on dialing in the correct torso size and strap positioning, which can lead to issues like chafing or hard-to-reach pockets if you get it wrong.

Order the right torso length — Atom Packs’ sizing guidance is worth spending time on before you click buy.

Organization & Features

The simple roll-top closure gives access to a big main compartment, with a top compression/gear strap, plus stretch pockets on the side, front, base, and the shoulder straps.

The Atom+ is actually a lot more practical and versatile than most stripped-back ultralight packs — the harness incorporates two shoulder pockets either side of the sternum strap that are super stretchy and big enough to hold most smartphones, soft flasks, or a fistful of trail bars.

The bottom pocket with its built-in trash port is a detail you won’t find on most packs. There’s a small corner of the bottom pocket that stays open so you can stuff your trash into it, plus a snap closure at the top instead of a loud Velcro strip. Small things, but they add up.

The lidless roll-top design takes a little getting used to — it’s better suited to organised hikers, since you’ll find yourself rooting around for a specific bit of kit otherwise.

Color-coded dry bags are your friend here.

Durability & Weather Resistance

The pack uses 210-denier Robic Extreema material on the side pockets, shoulder straps, and hip belt — an even more durable material in all the high-wear areas.

One thru-hiker used the same Dyneema-reinforced stretch mesh on the CDT and after nearly 3,000 miles it showed no signs of wear.

One reviewer took the Atom+ on the Welsh 3,000s, 200 miles on the PCT, and countless overnighters in Snowdonia, the Lake District, and Scotland through all seasons — with no delamination of the VX21, though the X pattern in the fabric became more prominent over time.

Weather protection is the one area where you need to manage expectations. While VX21 is highly waterproof, water can still get through the seams, so a DCF pack liner is strongly recommended to keep insulated layers and down quilts dry in heavy rain. The fabric’s waterproofing is reinforced with an eco-DWR finish, but seams are not taped, so water may still get in during prolonged exposure to rain. Budget for a pack liner — either Atom Packs’ own DCF option or a simple rubble sack.

Customization

Customization extends from selecting torso and hip belt dimensions to choosing colors for nearly all panels and materials for pockets. You can also specify shoulder strap and bottom pockets, top strap configuration, front elastic, side compression straps, and even the colors of the tabs that hold the front elastic — making designing a pack nearly as enjoyable as using it.

It’s genuinely rare at this price point.

The pack can get expensive with a lot of modifications, and lead times are currently long

— factor that into your planning if you’re targeting a specific trip.

Pros & Cons

Pros

• Carbon fibre frame punches well above its weight penalty — meaningfully better load transfer than frameless packs at a similar total weight
• Modular design: remove the hip belt, frame, and foam panel to strip roughly 5+ oz for lighter missions
• S-shaped shoulder straps are genuinely comfortable and work well for a wide range of body types
• Shoulder strap and bottom pockets are thoughtful, well-executed details most competitors skip
• Extraordinary customization options — fabric, color, pocket config, strap type, torso length
• Handmade by hikers, for hikers, from a small UK cottage operation with a strong quality track record

Cons

• Seams not sealed — a pack liner is a practical necessity in wet conditions, not an optional extra
• Removable hip belt can be tricky to re-seat correctly; requires some patience or a cardboard shim trick
• No load lifters; comfort starts to drop off noticeably as you approach 25 lbs
• Lidless roll-top requires organized packing discipline — poor fit for casual gear-dumpers
• Custom builds come with long lead times and cost can escalate quickly with add-ons
• Back panel provides minimal airflow — expect a sweaty back in warm weather

Who Should Buy This

The Atom+ is the right pack for hikers who’ve already dialed in a genuine ultralight kit and want a framed pack that doesn’t penalize them for it. You need to already have an ultralight setup — in terms of shelter, sleep system, and cook kit — otherwise you’ll struggle to get all your gear in and even if you do, it’ll be too heavy for a comfortable carry. It’s especially compelling for UK and European hikers who’d otherwise have to import from US cottage brands and pay the corresponding shipping and customs premium. It would perform well on something like the PCT, where a hip belt and extra pockets would be helpful in the Sierra but could be ditched in NorCal/Oregon where the terrain and carry demands ease off. If you frequently carry loads above 25 lbs or want a pack with serious load lifters and a structured suspension, look at the Atom Packs Prospector or something like the ULA Circuit instead.

Verdict

The Atom+ is one of the most compelling framed ultralight packs available, particularly for hikers based in Europe. The carbon fibre hoop genuinely earns its place — it keeps the pack honest under load in a way no frameless alternative can match at this weight — and the customization depth is almost unmatched in the cottage gear world. The unsealed seams and hip belt fussiness are real trade-offs, not dealbreakers. For a weight-conscious hiker with a refined kit, it’s a confident buy at 8.5/10.