Bottom Line
The Eco Summit Bum by ThruPacks is a thoughtfully designed bag that excels both as a standalone pack and as additional storage within larger gear systems.
Despite its compact size, it offers a spacious 2.5L capacity, complemented by an open stash pocket on the back and various organizational features to keep your items neatly arranged. Crafted from durable, waterproof EPX200 fabric, this pack is ideal for rainy-day adventures. The price tag feels justified, and it supports a small, US-based company.
While the main compartment provides ample space, the strap attachment is located toward the top of the pack, which can cause it to sag when loaded with heavier items. The non-fixed strap offers flexibility, making it easy to attach to a backpack or swap with a different hip belt. However, this convenience comes with a downside—it’s almost too easy to remove, and we’ve sent the pack tumbling off more than once. Additionally, the loose strap can make it uncomfortable when worn as a sling bag.
To see how this pack compares to the rest of our top-performing fanny packs, head over to CleverHiker’s guide to the best hiking fanny packs.
How We Tested
We use this fanny pack on several day hikes around Idaho, as well as on backcountry ski tours for accessible storage. Zippers were stress tested by overpacking and opening in quick succession to ensure there was no snagging. We also tested the durability and abrasion resistance of the fabric against 160-grit sandpaper, dirt, and hand-washing. Waterproofness was tested by simulating rain and performing a quick submersion test.
Quick Spec
Thrupack Eco Summit Bum
Best Fanny Pack for Additional Storage
CleverHiker Rating: 4.5/5.0
Price: $57-$65 (depending on pocket options)
Measured Weight: 3.7 oz.
Capacity: 2.5 L
Pros
- Weight-to-capacity ratio
- Padded waist
- 2" strap available
- Water-resistant
- Compatible with most backpack hipbelts
Cons
- Thin strap can be uncomfortable
- Sags when fully loaded
Comfort
The Eco Summit Bum is one of the most comfortable packs on our list, featuring a padded back and padded hip belt sleeve for added comfort. While we tested it with the standard 1-inch strap, ThruPacks also offers a Comfy Strap™ for an even cozier fit.
The pack’s rectangular, structured design maintains a sleek profile, even when carrying only a few items, and helps prevent shifting during use.
However, the hip belt lacks a fixed attachment, which allows the pack to easily slide along the webbing strap. While this design makes it simple to remove, it also causes the pack to shift around while hiking and makes it uncomfortable to wear as a sling bag.
During a trailside break, the pack unexpectedly slid off the belt and tumbled a few feet. For those who are careful with their gear, this is a minor issue, but it’s something to note if you’re a bit of a butterfingers.
Durability
Made with EcoPak EPX 200 fabric, the Eco Summit Bum withstood the abrasion test with minor wear and tear and hid the damage well. There were no broken threads or really any fuzzing. After being dragged through the dirt, it did take a little scrubbing with soap and warm water, but after cleaning, it showed no sign of holding stains.
There were no glaring issues with the durability of this pack during testing, but two things gave us pause in terms of construction. One end of the zipper was finished and seam taped, while the other side was simply bound with thread.
The webbing loops on the corners are sewn through the material, which on soggy days may eventually allow water to breach the otherwise waterproof material. Without seeing other ThruPack models, we can’t tell if this is an outlier – but is something to consider.
Features
The Eco Summit Bum is definitely weatherproof and passed our simulated rain and submersion tests without any water breaching the contents. Its zipper is high-quality, and the ergonomic zipper pulls keep fumbling to a minimum. This lineup has many options that integrate into larger pack systems, and the Summit Bum is the most straightforward one to attach. The padded strap sleeve allows compatibility with any strap up to 2” in width.
If you’d like to keep things off your waist, it does have additional attachment points to clip to your pack or your hip.
While it doesn’t have other fancy features like water bottle holders, the spacious main compartment can fit a 16oz bottle if you want to be totally hands-free.
Organization
Equipped with two inner pockets and a key clip inside the main compartment, as well as an open-stash pocket along the back – the Eco Summit Bum has room for your stuff and ensures you’ll be able to find it.
The back stash pocket felt more secure than other bags we tested with this feature, as the padding kept items snug in place. While our model lacked an exterior mesh pocket, ThruPacks offers several different designs and a custom bag maker to ensure you get the features you want.
On par with the organization systems on other bags with similar capacity, it doesn’t feel like the Summit Bum is particularly lacking in this category. One thing of note is that the key clip looked a bit like an afterthought, as it is simply tied to a plastic loop with string. On the other hand, if a key clip isn’t a deal breaker for you – this version will be easy to remove.
Should You Buy the Thrupack Eco Summit Bum Fanny Pack?
With its sleek, minimalist design and the ability to be customized with vibrant colors and patterns, the Summit Bum is equally at home at a festival as it is on the trail. While it may not be the most budget-friendly option for everyday carry, the price reflects its durability and quality, ensuring it will last for years of use. For those in search of a classic fanny pack design that can withstand the elements, this pack is a fantastic addition to your kit.
One standout feature is its versatility—it can easily be attached to your backpack or worn with clips, making it a great choice for various adventures, from thru-hiking to bikepacking. However, if you’re specifically looking for a bag that can comfortably double as a sling, you might want to explore other options. While the Summit Bum excels in other areas, it can be less comfortable in sling mode, especially during extended wear.
What Other Fanny Packs Should You Consider?
See comparable options below, or visit our complete guide to the best hiking fanny packs for all our favorites.
Hyperlite Mountain Gear Versa Review: For a pack that focuses on versatility of wear, check out the Versa. It is extremely comfortable when worn as a sling and was our top choice when it comes to backpack-compatible fanny packs. Although it is listed as having .25L less storage, the Versa feels like a blackhole and can hold much more than essentials. It does have a higher price tag, but that reflects the premium nature of the versa.
Zpacks F.U.P.A. Review: If the backpack integration is what piqued interest in the Summit Bum, the F.U.P.A by Zpacks is another good contender. It does have less capacity, so it tracks that the FUPA weighs an ounce less. Even with the smaller size, the height of the FUPA allows you to fit larger items with ease. It does help to have a Zpacks backpack or check that your buckles are compatible with the fixed ones on the pack.
High Tail Designs – the Ultralight Review: For another option for a sleek, no-frills pack with an interesting look – check out the Ultralight from High Tail Designs. While not customizable like the Summit Bum, there are so many color and pattern options – you aren’t likely to be twinning on the trail. It is in the same price range as the Summit Bum, so you are paying more for a smaller pack made from top-quality materials.
