Exo Mtn Gear K4 5000 vs Kuiu ICON 6 6000
Quick take: The Kuiu ICON 6 6000 costs $1 less; the Kuiu ICON 6 6000 carries more (98 vs 93 liters); the Exo Mtn Gear K4 5000 is lighter (5.8 vs 6.15 lbs).
Which one to buy
Proven or new is the choice between two $700 haulers, both sized for a week in the backcountry. Exo rates the K4 past 150 lb; Kuiu publishes no load rating for the ICON. The K4 5000 is an established platform with years of hard use behind it. The ICON 6 6000 is Kuiu's 2025 ground-up redesign, on a new 3D corrugated thermoplastic carbon frame built to yield rather than shatter, and it has no multi-season durability record yet.
Fit tips it for most buyers. Exo offers four frame heights and five hipbelt sizes plus a 30-day trial, so a wrong guess can go back. Kuiu has two frame heights and three suspension sizes, and owners warn its Regular frame runs short: hunters around 5 ft 9 in often end up with weight on their shoulders unless they size up to Tall. If you sit near that line, the Exo's finer steps are worth more than any feature on either spec sheet.
The Kuiu's case is the kit. Its $699 price includes two hip belts, a load sling, a rifle quick release, hipbelt pockets and a ventilated back, while the Exo's belt ships as bare MOLLE until you buy add-on pouches. For meat, the ICON opens roughly 5,000 cubic inches between bag and frame in load-sling mode and has a waterproof-coated drop pocket for up to 45 lbs of boned meat. The K4's flap-style shelf deploys without pulling the bag off the frame.
Each carries complaints worth knowing before you spend $700. On the K4, owners report harness or hipbelt slippage past roughly 60 lbs and a narrow bottom that fights bulky sleeping bags. On the ICON, only the main compartment is coated, the seams aren't sealed, no rain cover comes with it, and current Kuiu Pro owners can't reuse a single bag on the new frame.
Exo Mtn Gear K4 5000
Best if your torso falls between standard sizes or you can't try packs locally, since four frame heights, five belts and a 30-day trial make the fit easiest to get right.
Kuiu ICON 6 6000
Worth choosing if you want everything in the box, hipbelt pockets and load sling included, and you're comfortable betting on a frame design launched in 2025.
| Spec | Exo Mtn Gear K4 5000 | Kuiu ICON 6 6000 |
|---|---|---|
| Price | $700 | $699 |
| Rating | — | — |
| Type | Hunting Pack | Hunting Pack |
| Frame Type | External Frame | External Frame |
| Capacity | 93 L | 98 L |
| Weight | 5.8 lbs | 6.15 lbs |
| Max Load | 150+ lbs | Not published by the manufacturer |
| Torso Fit | 4 frame heights (22–26.5 in) with adjustable harness, 5 hipbelt sizes XS–XL | 3 suspension sizes (S/M, L/XL, XXL/3XL); Regular frame fits 5'2"-5'9", Tall fits 5'10"-6'6" |
| Material | MIL-SPEC 500D CORDURA with YKK zippers; built in Boise, Idaho | 330D double ripstop CORDURA nylon with waterproof-coated CORDURA main compartment |
| Back Panel | K4 carbon-fiber-stay frame with integrated load compression and flap-style load shelf | Patent-pending 3D corrugated thermoplastic carbon fiber frame (made in USA) with Flex-Forward geometry, breathable spacer air mesh and dual-density foam shoulder straps |
| Adjustable torso | Yes | Yes |
| Ventilated back | No | Yes |
| Raincover included | No | No |
| Hipbelt pockets | No | Yes |
| Removable lid | Yes | Yes |
| Hydration sleeve | Yes | Yes |
| Fits BV500 bear can | Yes | Yes |
| Warranty | Lifetime guarantee against defects, plus 30-day trial period | Kuiu warranty: defects in materials and workmanship for the practical lifespan of the product; original purchaser with proof of purchase, one repair or replacement per purchase |
Pros & cons
Exo Mtn Gear K4 5000
- ✓A long-term field reviewer called the K4 'the most comfortable pack tested' against the industry's best, crediting the custom carbon-stay frame and redesigned harness.
- ✓Fit options lead the category — four frame heights (22–26.5 in) and five hipbelt sizes (XS–XL), backed by a 30-day trial, versus pick-a-curve guesswork with Stone Glacier's Krux/Xcurve.
- ✓Organization is the K4's calling card: horseshoe zip into the main bag, stretch front panel, full-length zippered side pockets, and laser-cut MOLLE — owners say it's the easiest flagship pack to live out of.
- ✓The flap-style load shelf deploys without pulling the bag off the frame, making day-pack-to-meat-hauler transitions faster than Stone Glacier's unbuckle-everything approach.
- ✓The included lid adds ~650 ci and the price includes the complete system — no a-la-carte lid or frame math like Kifaru builds.
- ✓A dedicated hydration compartment with a drain grommet keeps a leaky bladder from soaking your sleep insulation, a detail forum users repeatedly call out.
- ✓Owners rate it 4.9 stars across 529 reviews on Exo's site (98% five-star), and the Boise-based customer service earns forum praise rivaling Mystery Ranch's.
- ✓Integrated bow and rifle carry work stock, and treadmill-style testing threads report no harness slippage running uphill with 30+ lb loads.
- ✗The bag tapers narrow at the bottom — owners report bulky sleeping bags like a Western Mountaineering Kodiak in its stuff sack fight to fit.
- ✗Several owners in the long-running K4 thread report harness or hipbelt slippage once loads pass roughly 60 lbs, requiring re-tensioning on pack-outs.
- ✗Side pockets use a single zipper that interferes with the lid when it's fitted — a two-zip design is a common owner wish.
- ✗Bow Spider users note the mount's metal clips don't line up with the K4 hipbelt MOLLE spacing, forcing workarounds for a popular accessory.
- ✗Hipbelt pockets aren't included — the MOLLE belt is bare until you buy Exo's add-on pouches, unlike some competitors' stock belt storage.
- ✗At 5 lb 13 oz complete with lid, it's the heaviest of the big-three frame systems — about half a pound over a Sky 5900 on the Xcurve frame and half a pound over a Metcalf 75.
- ✗The lighter K4X update (about 1 lb savings in prototypes) has limited release in summer 2026 with full launch in 2027, so buyers today are getting last-generation materials.
- ✗Exo sells essentially direct-only, so outside the 30-day trial there's no trying one on in a store the way Scheels stocks Stone Glacier and Mystery Ranch.
Kuiu ICON 6 6000
- ✓At 6 lb 2.4 oz for the complete 98 L kit, it undercuts comparable Kifaru and Mystery Ranch expedition haulers by a pound or more while keeping a genuine load-hauling frame.
- ✓The 3D corrugated thermoplastic carbon frame is engineered to yield rather than shatter — a direct answer to the cracked carbon frames owners reported on the old Pro system.
- ✓Load-sling mode opens roughly 5,000 cubic inches between bag and frame for quarters, and the Pack Load Hauler doubles as a glassing pad for direct on-frame meat hauls.
- ✓$699 buys the entire kit — frame, bag, two hip belts, load sling, rifle quick release and gear strap — while owners note comparable Exo K4 and Stone Glacier builds push north of $800.
- ✓The horseshoe zipper across the back panel lets a rifle or a whole elk quarter slide down against the frame without unloading the bag, a feature early reviewers single out.
- ✓An internal waterproof-coated drop pocket carries up to 45 lbs of boned-out meat high and tight against the frame, keeping the weight where the suspension can handle it.
- ✓Hook & Barrel's tester found the suspension 'began to distinguish itself around the 80-pound mark' with zero frame creak or squeak — a common gripe on older Kuiu carbon frames.
- ✓Nearly five inches of half-inch-increment shoulder adjustment plus Regular and Tall frame heights covers hunters from 5'2" to 6'6", with a dedicated women's version.
- ✗Zero backward compatibility — Kuiu states the ICON 6 'shares zero key components' with the Pro/Pro LT systems, so existing Kuiu bag owners must rebuy everything.
- ✗Some experienced owners still say Kuiu frames aren't at Stone Glacier or Kifaru level for comfort under loose meat and heavy quarters.
- ✗It's a brand-new 2025 system with essentially no multi-season durability record, versus the proven Exo K4 and Stone Glacier Xcurve platforms it competes with.
- ✗Kuiu's 'Regular' frame sizing historically runs short — several owners warn hunters around 5'9" and up end up with weight stuck on their shoulders unless they size up to Tall.
- ✗Only 7 verified reviews existed on Kuiu's site as of mid-2026, so crowd-sourced validation is thin compared to packs with hundreds of reviews.
- ✗No rain cover is included; the uncoated weight-saving panels and unsealed seams mean a soaked pack in sustained downpours without a liner.
- ✗At $699 the kit costs $100 more than the outgoing Pro 6000, and it's over twice the weight of ultralight crossover haulers like Seek Outside's Divide if you don't need the full 98 L.
Exo Mtn Gear K4 5000 vs Kuiu ICON 6 6000: common questions
Which is the safer buy if I'm around 5 ft 9 in?▾
The K4 5000. Owners warn that Kuiu's Regular frame, listed for 5 ft 2 in to 5 ft 9 in, runs short and leaves weight on the shoulders. Exo's four frame heights from 22 to 26.5 in give finer steps, and the 30-day trial covers a wrong pick.
Will I need to buy extras for either pack?▾
Probably for the Exo: its belt is bare MOLLE, so budget for Exo's add-on pouches. The Kuiu kit already includes hipbelt pockets, two hip belts, a load sling, a rifle quick release and a gear strap. Neither one comes with a rain cover.
Which handles boned-out meat better?▾
The Kuiu has more dedicated hardware: a load-sling mode between bag and frame plus a waterproof-coated drop pocket for up to 45 lbs of boned meat. The K4's flap-style shelf deploys without removing the bag, but owners report belt slippage once loads pass roughly 60 lbs.