ULA Catalyst vs Gossamer Gear Gorilla 50
Quick take: The Gossamer Gear Gorilla 50 costs $10 less; the ULA Catalyst carries more (75 vs 50 liters); the Gossamer Gear Gorilla 50 is lighter (1.95 vs 2.65 lbs).
| Spec | ULA Catalyst | Gossamer Gear Gorilla 50 |
|---|---|---|
| Price | $300 | $290 |
| Rating | 4.8★ (400) | 4.6★ (300) |
| Type | Ultralight Pack | Ultralight Pack |
| Frame Type | Internal Frame | Internal Frame |
| Capacity | 75 L | 50 L |
| Weight | 2.65 lbs | 1.95 lbs |
| Max Load | 40 lbs | 30 lbs |
| Torso Fit | S: 15-18 in, M: 18-21 in, L: 21-24 in | Sized S-L, 14.5-21.5 in |
| Material | ULA 400 Robic nylon | 100D/200D Robic nylon |
| Back Panel | Foam panel with carbon-fiberglass hoop and dual stays | Removable sit-pad with aluminum stay |
| 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 | Gossamer Gear limited lifetime |
Pros & cons
ULA Catalyst
- ✓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.
Gossamer Gear Gorilla 50
- ✓The archetypal 'graduation pack' — the r/Ultralight cliché is buying a Mariposa, shrinking your kit, then buying a Gorilla.
- ✓Under 2 lbs with a real stay and hipbelt, it carries 30 lbs honestly — better than frameless rivals at similar weight.
- ✓Symmetric pockets fix the Mariposa's polarizing layout while keeping generous capacity.
- ✓The removable sit-pad back panel remains one of the smartest dual-use designs in UL.
- ✓Robic fabric durability matches its big sibling's strong track record.
- ✓Mixed torso/hipbelt sizing gives semi-custom fit off the shelf.
- ✓A BV450 fits cleanly; careful packers manage a BV500 vertically.
- ✓Gossamer Gear's service reputation applies here too.
- ✗50 liters is tight for bear-canister trips or 5+ day food carries — buyers routinely wish for 5 more liters.
- ✗Same sweaty foam back as the Mariposa.
- ✗The 30 lb ceiling is real; water-heavy desert carries overload it.
- ✗Fixed sizes, online-only fitting.
- ✗Mesh pockets remain the wear point in brush.
- ✗The hipbelt is minimal and divides opinion at the top of the load range.
- ✗No lid, no organization beyond the pocket array.
- ✗Price sits close enough to the Circuit that many first-time buyers default to ULA's bigger volume instead.