ULA Circuit vs ULA Catalyst

ULA Equipment

ULA Circuit

$280

4.9★ (700)

ULA Equipment

$300

4.8★ (400)

Quick take: The ULA Circuit costs $20 less; the ULA Catalyst carries more (75 vs 68 liters); the ULA Circuit is lighter (2.33 vs 2.65 lbs).

Spec	ULA Circuit	ULA Catalyst
Price	$280	$300
Rating	4.9★ (700)	4.8★ (400)
Type	Ultralight Pack	Ultralight Pack
Frame Type	Internal Frame	Internal Frame
Capacity	68 L	75 L
Weight	2.33 lbs	2.65 lbs
Max Load	35 lbs	40 lbs
Torso Fit	S: 15-18 in, M: 18-21 in, L: 21-24 in	S: 15-18 in, M: 18-21 in, L: 21-24 in
Material	ULA 400 Robic nylon	ULA 400 Robic nylon
Back Panel	Foam panel with carbon-fiberglass hoop and internal stay	Foam panel with carbon-fiberglass hoop and dual stays
Adjustable torso	No	No
Ventilated back	No	No
Raincover included	No	No
Hipbelt pockets	Yes	Yes
Removable lid	No	No
Hydration sleeve	Yes	Yes
Fits BV500 bear can	Yes	Yes
Warranty	ULA lifetime against defects	ULA lifetime against defects

✓Has topped the Halfway Anywhere PCT gear survey for years — no pack has more verified thru-hiking miles behind its reputation.
✓Owners routinely report 3,000-5,000 trail miles before meaningful wear; the 400d Robic build is the UL durability benchmark.
✓The 68L total volume (bag plus huge pockets) swallows a BV500 plus a week of food, which smaller UL packs can't.
✓Carries its full 35 lb rating honestly — the hoop-and-stay frame outperforms most packs in its weight class.
✓The giant mesh front pocket and dual oversized hipbelt pockets define the category's organization standard.
✓Hand-made in Utah with a service team famous for repairs, spare parts, and straight answers.
✓The roll-top plus Y-strap handles bear canisters, foam pads, and packrafts without drama.
✓Resale value is exceptional — used Circuits sell within hours on UL trade forums.

✗The foam back panel has zero ventilation; expect a soaked shirt on humid climbs.
✗Fixed torso sizing means no adjustment range — measure carefully before ordering.
✗The utilitarian look (and famously loud color options) is a running joke even among loyalists.
✗At 2.33 lbs it's now heavier than newer rivals like the Kakwa 55 that match its carry.
✗No lid and minimal internal organization — everything lives in stuff sacks or the main tube.
✗Direct-order only in the US; you can't try one on in a store.
✗Lead times stretch during thru-hiking season, sometimes badly.
✗The J-curve shoulder straps don't suit every chest shape; some switch to S-straps aftermarket.

✓The go-to answer when r/Ultralight asks 'what if I need more than a Circuit' — same DNA, more capacity, 5 lb higher rating.
✓Dual aluminum stays plus the hoop make its 40 lb rating honest; desert hikers carry 8L of water without collapse.
✓75 liters swallows a BV500 horizontally plus 10 days of food — the specific use case owners buy it for.
✓The same 400d Robic bombproof reputation as the Circuit, with thousands-of-miles reports common.
✓Massive front mesh and hipbelt pockets keep a full day's needs outside the main bag.
✓Hand-made in Utah, easily repairable, backed by ULA's excellent service.
✓Only 5 ounces heavier than the Circuit for 7 more liters and a stiffer frame.
✓Strong resale on trade forums, like everything ULA.

✗Overkill for standard three-season loads — most buyers who don't need the volume end up wishing they'd bought the Circuit.
✗Same zero-ventilation foam back as the Circuit; sweat is the tax.
✗Fixed torso sizes with direct-order-only sizing risk.
✗At 2.65 lbs it's approaching crossover packs with plusher harnesses.
✗The big collar is floppy when underfilled, so partial loads need diligent compression.
✗No lid, no internal organization — the usual ULA minimalism.
✗Seasonal lead times can be long.
✗The look is pure function; nobody buys a Catalyst for style.