The Exped Thunder 70 is an internal frame backpack with an adjustable frame and panel loading access. Weighing 3 pounds 6 ounces (tested), it has a very comfortable hip belt which ensures excellent load transfer to the hips and a single external aluminum stay which prevents torso collapse with heavier loads. With daisy chains and numerous external attachment points, the Thunder 70 can be outfitted for a wide range of trips from extended backpacking and winter hiking trips to adventure travel.
Internal Storage and Organization
The Exped Thunder 70 has a classic alpine style pack design with a top floating lid, large main compartment and extension collar.
The main compartment can be accessed through the top of the pack using a conventional drawstring closure, but there are also two zippers along the back that provide panel style access to items anywhere inside the main compartment without pulling them out of the top. This is handy for big loads or when using the pack for travel. When pulling down the back panel, the side compression straps must be released.
The side access zippers are covered with wide rain flaps but do not have a zipper guard inside, so care must be taken when closing them to prevent snags with dellicate fabric or stuff sacks. The top of the back panel secures to the pack with a wide velcro strip and has a wide rain awning covering it, however, it is possible for rain to leak into the main compartment if all of the components are not aligned properly, and through the seams which perforate the back of the pack. If hiking in rainy weather, my advice would be to line the inside of the pack with a trash bag or use waterproof stuff sacks for sensitive items.
In addition to panel access, each of the side zippers can be pulled down individually and items extracted or stuffed into the main compartment, as shown. This does not require unhooking the side compression straps and is possible when the pack is not loaded down with externally attached gear.
The main compartment can fit a black Garcia bear canister positioned horizontally, with plenty of room for extra gear. There is also a separate hydration pocket on the back panel of the pack, inside the main compartment.
External Storage and Compression System
With two side stretch mesh pockets, a rear shovel pocket, and large hip belt mesh pockets, the Exped Thunder 70 has an ample amount of convenient external storage for water bottles and gear you want close to hand.
The pack has two tiers of compression straps, including a set that can be threaded through the water bottle pockets, providing compression even if the pocket contains a bottle. The compression straps are also long enough to accommodate snowshoes strapped to the side of the backpack, although doing so renders the side pockets difficult to access.
Exped has chosen to use aluminum hook rather than plastic buckles to anchor all of the webbing straps on the Thunder 70 (with the exception for the torso adjustment strap). These hooks can be difficult to adjust in cold weather while wearing gloves but are adequate for securing gear as long as there is good tension on the straps.
There are two daisy chains running down the back of the pack, which include elastic shaft holders, and provide users with the ability to strap all kinds of external gear to the back of the pack, provided they have additional straps to attach it with. There are also numerous tie-outs around the perimeter of the top lid and at the base of the pack for lashing on additional gear.
The Exped Thunder 70 can be adjusted for people with different torso lengths, by raising or lowering the shoulder straps along the central aluminum stay which runs up the center of the pack. While this system works well when the proper fit is dialed in, the lack of sizing information on the webbing strap can make the fitting process difficult for less experienced pack users who don’t know how to tell if the distance between the shoulder harness and the hip belt “feels” too long or too short. It’d be nice is the webbing strap was labeled with numbers that indicated torso length in inches and centimeters.
The only “frame” element on the Thunder 70 is the central aluminum stay, shown above. Despite this, the pack performs admirably with heavy loads, with little noticeable lateral sway or torso collapse when heavily loaded. Load transfer to the hips is excellent, in part because the hip belt is attached directly to the base of the stay, and because the pre-curved foam padding provides excellent contact with the hips, The fit of the hip belt is also enhanced by the use of a Scherer cinch (tightened by pushing the hip belt straps forward), which provides mechanical advantage for getting a better fit.
The shoulder pads are narrow but well padded, providing a comfortable fit for people with narrow shoulders. Both shoulder straps have load lifters, including front buckles for adjusting their angle when the shoulder harness is raised or lowered. The shoulder harness itself is minimal, and only touches the top of the wearer’s shoulders and back, good ventilation for keeping sweating at bay. External attachment options on the outside of the shoulder straps are somewhat limited however (a plastic loop is provided) and users may need to augment the straps with tri-glides in order to hang accessory pockets if a horizontal strap is required to connect them.
- Hip belt is extremely comfortable and provides excellent load transfer because it is attached to the central aluminum stay
- Front anchor of the load lifter straps is adjustable, ensuring the ability to keep load lifters at a 30-45 degree angle when the torso length of the pack is adjusted. This is a high-end feature, normally only found on expedition class backpacks.
- Tapered main compartment and hip control straps helps ensure a very stable carry, despite the fact that the pack only has a single central frame stay.
- Bottom compression straps can be threaded to run through inside of the side mesh pockets or outside, enabling compression when carrying water bottles, or external gear attachment (such as snowshoes).
- Velcro webbing keepers help keep the numerous straps under reasonable control
- No torso length information on the webbing strap which controls torso length, so users have to be fairly experienced to determine whether the torso length is adjusted correctly or not.
- Hip belt runs a bit small for a size 38″ waist.
- Top lid slumps back and off-center when the main compartment is not fully loaded. This is a common problem with alpine style packs with a floating lid.
- No bottom reinforcement on side stretch mesh pockets making them more prone to tearing on vegetation.
The Exped Thunder 70 is an extremely comfortable and versatile high volume backpack that can be outfitted for many different types of adventures, ranging from backcountry trips to more urban front country adventures. Featuring convenient rear panel gear access, the Thunder is ideal for multi-sport trips that require different clothing or equipment at different times, such as climbing or mountaineering trips that require long approach hikes followed by sport-specific activities. Weighing just 3 pounds 6 ounces, the Thunder 70’s unique shoulder harness, hip belt and aluminum stay system provide exceptional load carrying capabilities for a backpack of its size. The Thunder 70’s hip belt is one of the best I’ve ever used and I’m difficult to impress.
- Made with 210 Dyneema Grid Check and Stretch Mesh
- 70 liter capacity (covered storage)
- Available in Men’s and Women’s models
- Adjustable torso length
- External stay
- Two stretch mesh side water bottle pockets with pass-through compression webbing
- Front stretch mesh pocket
- Two front daisy chains
- Floating lid with one external and one internal pocket
- Top rope carrying strap
- Spindrift collar
- Hydration pocket
- Dual ice axe loops with elastic shaft holders
- Hip belt with scherer cinch and lumbar pad
- Two stretch mesh hip belt pockets
- Two tiers of compression straps
- Load lifters with front angle adjustment
- Adjustable sternum strap
- Webbing cord keepers
- Aluminum hooks instead of plastic buckle
- Numerous external attachment points on pack body and lid
Disclosure: Exped provided Philip Werner with a sample Thunder 70 backpack for this review.SectionHiker is reader-supported. We only make money if you purchase a product through our affiliate links. Help us continue to test and write unsponsored and independent gear reviews, beginner FAQs, and free hiking guides.