The world's most in-depth and scientific reviews of gear

How We Tested Day Packs

Thursday June 25, 2020

We used and abused these packs while hiking, climbing, bushwhacking, and snowshoeing all over the rugged Washington Cascades and Seaward Kaikoura Range of New Zealand. We used them daily to carry our things around town and to the crag or gym. We used multiple packs side-by-side in demanding conditions to see which would rise to the top. We also applied some rigorous science to measure and test these bags side-by-side, which we detail below.

We put these daypacks through the ringer in all conditions
We put these daypacks through the ringer in all conditions

Comfort


We used each of these packs in a range of outdoor activities, including hiking, running, scrambling, climbing, bushwhacking, and snowshoeing. Throughout these activities, we evaluated how comfortably these packs carried their loads and transferred load through their suspension. For larger packs suited to carrying heavy loads, like the REI Co-op Traverse 35, we even went backpacking and hauled a few dozen pounds of rock samples out of the mountains of New Zealand (our lead tester is a geologist). While pushing these packs slightly outside of their intended use with aerobic activities like bushwhacking and running, we evaluated how well their suspension ventilated and allowed our sweaty backs to stay cool. We did these activities with others and frequently gave out packs to them to evaluate how well they could adjust to varying torso sizes and get other perspectives on their performance.

The Traverse carries pretty much anything you could think to bring on a day trip  and it does so comfortably and conveniently.
The Traverse carries pretty much anything you could think to bring on a day trip, and it does so comfortably and conveniently.

Finally, we devised a standardized calisthenics test to rigorously evaluate comfort side-by-side. We loaded packs with a typical day hiking load, ensured the pack was properly fit, and compressed each pack if compression straps were present. We then hefted each pack and did six push ups with rotation to side plank, 15 seconds of high knees, two pull ups, lateral and forward leans from the hips, and left and right rotation from the hips. During these activities, we noted whether packs hugged our torso or slipped, as well as how much each pack restricted our range of motion (e.g., when reaching up to do a pull up). Packs that performed well in this calisthenics testing did not slip at all and only slightly restricted our range of motion.

The Flash 22 performed well in our calisthenics testing. While this isn't real-world use for most people  it's a great standardized test of load-carrying stability.
The Flash 22 performed well in our calisthenics testing. While this isn't real-world use for most people, it's a great standardized test of load-carrying stability.

Weight to Volume Ratio


While pack weight is important, larger packs are almost sure to be heavier than smaller packs, and we test packs for this review that range from 15 to 48 L capacity. To account for this, we computed a weight to volume ratio (oz/L) and ranked packs based on that ratio. Essentially, this measures the "bang for your buck" in terms of how much a pack can hold for its weight.

To give context to these measurements, we also evaluate the features and materials that contribute to a pack being light or heavy for its volume.

This pack is surprisingly comfortable for its ultralight weight. Even running  it didn't shake around.
This pack is surprisingly comfortable for its ultralight weight. Even running, it didn't shake around.

Versatility


In the field, we tried to use these packs for a range of activities. We considered packs as being versatile if they could perform well for multiple outdoor pursuits, or at least a couple outdoor pursuits as well as travel or commuting. By carrying specialized gear like snowshoes, ice axes, and hiking poles, we evaluated whether packs had the attachment points needed for certain activities.

The stretchy mesh pockets hold a lot of stuff and don't impede the other features of the pack.
The stretchy mesh pockets hold a lot of stuff and don't impede the other features of the pack.

Ease of Use


A good pack should be simple and easy to use. In our field testing, we evaluated how easy it was to get to items stored in various parts of the pack, the number of pockets available for organization, the functionality of specialized carrying attachments (e.g., shoulder strap pole holders), and the quality of the design of those features.

The Stratos 34 lacks some common straps tat are useful for carrying bulky objects like snowshoes. However  its panel loading design makes it easy to access the main compartment even when lots of things are attached to the outside
The Stratos 34 lacks some common straps tat are useful for carrying bulky objects like snowshoes. However, its panel loading design makes it easy to access the main compartment even when lots of things are attached to the outside

Durability


We did our best to put these packs through the wringer in the months we spent with them. However, we can't evaluate long-term durability without spending years with these packs. We draw on market research, our years of experience abusing various backpack materials and construction types, and the bangs and scrapes that we dish out to these packs in our field testing to estimate their durability.

Even this lightweight pack held up well for a day of scrambling.
Even this lightweight pack held up well for a day of scrambling.

We also use a standardized water-resistance test to evaluate how well these packs deal with rainy conditions. We filled packs with towels, put on their rain covers (if they came included) then sprayed them down with a hose for three minutes, attempting to spray from all sides other than the suspension (which would be against your back). After three minutes, we took off the rain covers, checked the towels for dampness, then sprayed the packs for another three minutes without rain covers. Packs that performed well at this test did not let any water in with their rain cover on, and only a little after three minutes of intense spray without their rain cover.

We test packs side-by-side to see how they measure up in all conditions. This includes a standardized rain test to evaluate wet-weather performance.
We test packs side-by-side to see how they measure up in all conditions. This includes a standardized rain test to evaluate wet-weather performance.