25th Anniversary Green ULTRA 400X Circuit
1. TORSO FIT
- Standing upright, tilt your chin to your chest.
- Locate your C7 Vertabra—the large lump at the base of your neck.
- With flexible tape, measure down the length and natural curvature of your spine to your iliac crest/ the top of your hipbone.
- This measurement in inches is your torso length.
TIP: If you're between 2 sizes, order the smaller size. Still not sure? Contact us.
2. TORSO CHART
We've found most people in these height ranges fall into these torso/pack sizes. That being said, it is always best to measure your torso using the guide above.
If you're between sizes and you are getting a FRAMED pack, we recommend you size DOWN!
If you're between sizes and you are getting a FRAMELESS pack, we recommend you size UP!
If you have questions, or your torso size doesn’t seem to make sense for your height, please contact us.
3. HIPBELT FIT
Use the following method to determine your hipbelt inches, then head to Step 4 to see the hipbelt size you need.
MEN
Pant Waist Size + 2".
WOMEN
CURVY HIPS: Smallest part of your waist + 5".
STRAIGHT HIPS: Smallest part of your waist + 3".
KIDS
Smallest Part of waist + 2".
4. HIPBELT SIZE CHART
Find the hipbelt measurement you calculated in Step 3 on the chart. That will be your hipbelt size.
TIP: If you are on the outer edge of a size, order the larger size. [ Ex: If you are 38", you will notice 38" is the last number of the Medium Hipbelt and the first number of the Large Hipbelt. You would want to order a Large.]
5. SHOULDER STRAPS
The downward slope of your shoulder profile usually determines strap preference. You can assess your shoulder slope profile by looking in a mirror or having a friend look at the angle of your shoulder from the base of your neck to your shoulder point.
If there is relatively little or no downward slope, you have what is referred to as flat or squared shoulders.
If there is a noticeable downward slope, you have what is referred to as standard or sloping shoulders.
J STRAPS
J-straps are the traditional straight straps. They are best suited for people with flat or square shoulders, as their flat shape provides better surface contact and less rub.
S STRAPS
S-straps contour body curves. They are best suited for people with standard or sloping shoulders, as their contoured shape better hugs your shoulder slope.
TIP: If you have a short torso but a larger upper body, you may need a slightly longer strap. If you are very large in the upper body, you might need XL shoulder straps. Contact us, and we would be happy to make these customizations so your pack is comfortable and fits well.
$379.99
MADE IN THE U.S.A.
FREE U.S. DELIVERY OVER $50
LIFETIME WARRANTY*
TUNE-UPS & REPAIRS*
Description
For 25 years, we’ve been blessed to adventure with you.
Across deserts and over alpine passes. From the first time your feet touched a trail to the confident (yet weary) final steps of a thru. From the PCT, AT, and CDT, to all the unnamed trails in between, we’ve been there, cheering you on.
What began as one man, a sewing machine, and an idea has grown into a global community of hikers who trust us with their biggest dreams.
Since its debut in 2006, the Circuit has been a trail favorite. Year after year, it’s earned Best Gear awards. For more than a decade, it’s remained one of the most popular packs on the Pacific Crest. It’s the one hikers return to, again and again.
To celebrate 25 years on the trail, we’ve built something to commemorate our history and the friendships we’ve built along the way.
This limited 25th Anniversary Edition Circuit returns to our roots in Green (a nod to ULAs long-standing love affair with green Robic!) while embracing modernity with ULTRA 400X, one of the most advanced ultralight backpacking materials.
Heritage details include a classic open static mesh front pleated pocket with elasticized top closure and original gray grosgrain shockcord tabs. Of course, it had to be green!
The 25th Anniversary Edition also includes UltraGrid side pockets, a built in 5/8″ top Y-strap closure, and ULTRA hipbelt pockets with YKK AquaGuard zippers.
In true ULA fashion, we’ve built it with only the best materials and construction.
New tech meets old aesthetics.
This is 25 years of evolution and obsession, stitched into one pack.
ULA Circuit
Whether you’re heading out for the weekend or thru-hiking a long trail, the ULA Circuit has you covered. A long-time award winner and one of the most popular packs on the PCT for well over a decade, the Circuit has earned its reputation mile by dusty mile. If your total pack weight is around 30 pounds or less and you’re ready to feel the freedom of traveling light without sacrificing comfort, the Circuit is for you.
The Circuit wasn’t just built to be ultralight; it was built to be comfortable. Our internal suspension system pairs a carbon fiber and Delrin® suspension hoop with a single aluminum stay to provide excellent load transfer, rigidity, and trail stability. A padded backpanel adds structure and cushion where you need it most. The removable pass-through hipbelt ensures proper weight transfer to your hips, while contoured shoulder straps and a sternum strap dial in fit and stability. The result? A pack that’s comfortable all day long.
The Circuit is built to adapt to your gear with each new adventure. A rolltop closure with built in 5/8″ Y-top strap allows for expandable volume, while side compression straps keep loads secure and dialed in. Ice axe and trekking pole loops come standard. Built in low-profile attachment points let you add optional bottom straps for strapping gear externally. Angled UltraGrid side pockets keep hydration within reach without stopping. UltraGrid hipbelt pockets with YKK AquaGuard zippers are big enough to hold most phones, snacks, and all the other “must-haves” on trail. The front shock cord system and pleated, open static mesh pocket with elasticized top closure offer quick-access storage for water purification, layers, and more.
Why ULTRA? ULTRA fabrics offer exceptional strength-to-weight performance, with woven UHMWPE fibers that are 15x stronger than steel by weight, highly abrasion-resistant, and waterproof to 200 psi. By strategically reinforcing high-wear areas and balancing durability with weight savings, we’ve created a pack that’s built for years of use.
To maximize overall water resistance, the 25th Anniversary Green ULTRA Circuit does not include a hydration hose port.
The ULA Circuit: always adventure-ready.
Winner of the 2023 Adventure Alan Best Gear Award. Winner of The Trek 2023 Best Gear Award. Winner of the Treeline Review 2024 Best Gear Award. The most popluar pack on the Pacific Crest Trail for four years running and the 2023 most used pack on the CDT according to the Halfway Anywhere Annual Survey of PCT Thru Hikers.
Specifications
| Weight | ||
| Based on Size Medium: | 38.5 oz. | 1,091 g | |
| Capacity | ||
| Recommended Max Load | Sub 35 lbs | |
| Total Pack Volume | ||
| Total Capacity | 4,200 CI | 68 L | |
| Volume Breakdown | ||
| Compartment | Cubic Inches (CI) | Liters (L) |
|---|---|---|
| Main Body | 2,400 CI | 39.3 L |
| Front Mesh Pocket | 400 CI | 6.6 L |
| Left Side Pocket | 400 CI | 6.6 L |
| Right Side Pocket | 400 CI | 6.6 L |
| Extension Collar | 500 CI | 8.19 L |
| Left Hipbelt Pocket | 91.5 CI | 1.5 L |
| Right Hipbelt Pocket | 91.5 CI | 1.5 L |
AT A GLANCE
WEIGHT: 38.5 OZ | 1,091 GM
VOLUME: 4,200 CU IN | 68 L
MAX LOAD: 35 LBS | 16 KG
FEATURES
- Limited Color: ULTRA 400X Green
- Heritage: Open Static Mesh w/ Elasticized Top Closure
- Heritage: Gray Grosgrain Shockcord Tabs
- Ice Axe/Trekking Pole Loops
- Low Profile Loops for Removable External Straps
- Built in 5/8″ Y-top Closure
- ULTRA Hipbelt Pockets w/ YKK AquaGuard Zippers
- UltraGrid Side Pockets w/ Elasticized Top
- Internal Suspension Hoop
- Rolltop Closure
- Side Compression Straps
- Sternum Strap
- Contoured Shoulder Straps
- Front Shock Cord
- NO Water Hose Port for Max Water Resistance
- Removable & Height Adjustable Pass-through Hipbelt
- Padded Backpanel
FAQ’S
Q: WHY ULTRA™?
A: ULTRA is 15x stronger than steel by weight, twice as abrasion resistant as standard 420D nylon, and waterproof to 200 psi. Ultra is the ultimate in ultralight fabric, with the strength to go the distance in the harshest environments.
ULTRA fabric lasts longer, absorbs 80% less moisture, and has better UV resistance and color retention than traditional laminated nylon.
ULTRA is the only durable, waterproof pack fabric made from 100% recycled polyester! Every yard contains over 20 plastic bottles and saves over one pound of carbon emissions compared to standard pack fabric.
Q: WHAT IS A SUSPENSION HOOP?
A: The suspension hoop used in the Circuit is our minimal solution to transferring load between shoulder and hip. If you imagine an upside ‘U’ you get a sense of how the hoop is positioned and how it functions. The upper arch of the ‘U’ ties into the shoulder straps, while each leg of the ‘U’ ties into the hipbelt. These points of contact allow for a range of suspension flexibility while being rigid enough to support loads up to 35 lbs. In addition, because the suspension is located on the periphery of the pack body, and the back-panel is stiffened slightly with dual density foam, the result is a pack that can handle the load but does not dictate your body’s movements — but rather responds to how you move. Personally, when the loads are kept below 35 lbs, we find this pack to be the most comfortable in the ULA line-up.
Q: CAN A BEAR CANISTER FIT IN THE CIRCUIT?
A: Every bear canister on the market will fit into the Circuit vertically and some smaller bear canisters will horizontally. Keep in mind it is best to pack something between the hard sided canister and the bottom of the pack.
To see a chart showing what bear cans fit in what ULA packs (and how), visit our blog post “Bears! Everything You Need to Know About Backpacking in Bear Country.“
Q: WHERE DO I STRAP MY SLEEPING PAD?
A: A foam pad can easily be secured to the top of the pack by adding a Top Y-strap Kit to your order, to the bottom of the pack by adding a Bottom Strap Kit, or get Both and keep your options open!
If you’re using an inflatable pad, we recommend storing it in the pack’s interior to avoid punctures.
Q: CAN A WATER BOTTLE FIT IN THE SIDE POCKETS?
A: Each side pocket can accommodate two 1-Liter ‘Big Slam’ style bottles. A Nalgene-style bottle will also fit, but in your quest to lighten up, that should have been replaced a long time ago! In general most people can reach back and retrieve a bottle, drink, and return the bottle to the pocket without removing the pack. The top of the side pockets are angled for easier access.
Q: HOW DOES THE TOP OF THE PACK STAY CLOSED?
A: The top of the pack closes like a dry bag (also known as a rolltop) very similar to what river runners use to create a water resistant seal for their gear bags. The back of the collar is slightly taller than the front. Once you are packed, the collar can be rolled down upon itself to effectively create a barrier to water penetration. Once rolled, each side of the collar can be buckled to the sides of the pack or the two yellow buckles on the top can also be fastened to each other.
As for access, once the collar is rolled and fastened shut, you would need to unbuckle the compression straps and unroll the collar to access the inside of the pack. However, the roll-top only needs to be rolled shut when the weather dictates. If the sky is dry, the collar can simply be folded forward. Vertical compression can still be achieved by buckling the collar to the sides of the pack.
WHAT PEOPLE ARE SAYING…
Happy Hike-iversary.
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