Review: Aer Delivers the Ultimate Crossbody Travel Bag with the Day Sling 3

Since the brand’s inception in 2014, Aer has built a name for itself on the strength of its streamlined, yet thoroughly rugged and utilitarian bags. Renowned for its spartan design language, premium hardware, and its signature 1,680-denier CORDURA construction, Aer’s basic formula has undeniably led to some incredible backpacks and duffels, so when the company announced the release of its third-generation travel-focused sling-style pack this past spring, we became eager to see what new innovations Aer would be bringing to the crossbody bag space. In an effort to find out for ourselves, we’ve sourced the San Francisco-based label’s latest sling bag to deliver this hands-on review of the Aer Day Sling 3.

Right out of the box, the first thing you’ll likely notice about Aer’s third-generation Day Sling is its unmistakably rugged and high-quality shell construction — an area made all the more evident by the compact bag’s fairly hefty 0.8lb (12.8oz) weight. In a similar vein, the Day Sling 3’s seams are all noticeably reinforced, and all of the bag’s hardware and trim boast a robust quality that you can feel. Despite this, the crossbody bag doesn’t look particularly bulky and could easily pass for a regular, more lightweight sling — while being markedly more hardwearing and no less utilitarian.

In typical Aer fashion, the Day Sling 3 boasts a shell that’s crafted from a ballistic-grade 1,680-denier CORDURA nylon — and is bluesign approved. While this high-denier material may seem a bit overkill for a small sling pack, the 1,680D CORDURA makes for an exceptional shell that, while soft, provides enough rigidity to give the Day Sling 3 its own free-standing structure and shape, even when devoid of contents. Aer also produces an even more rugged and high-end version of its third-gen Day Sling that sees the standard model’s already highly-durable 1,680-denier nylon construction jettisoned in favor of an X-Pac VX-42 sailcloth shell.

Despite the Day Sling 3’s minimalistic aesthetic, the exterior of the pack actually possesses quite a few subtle yet noteworthy features. On top of being outfitted with custom Aer-branded plastic pulls, the sling’s zippers all consist of fully-weatherproof YKK items that keep the bag’s contents dry, even in the heaviest of downpours. Aer’s Day Sling 3 also sports a webbing-style, adjustable crossbody shoulder strap with an automatic-coupling, magnetic FIDLOCK buckle, as well as a beefy nylon grab handle — both of which feature heavy reinforcements at their connection points with the sling. What’s more, Aer has also opted to bestow the bag with hardwearing Duraflex plastic hardware.

Measuring 11.5″ L x 6” W x 3” D,  the Day Sling 3 sports a trio of pockets that all feature a soft-woven lining that protects the bag’s contents while also providing a bit of contrast to make it easier to find internal items. What makes this sling special, however, is the fact it manages to offer a whopping three liters of storage space — substantially more than your average sling — without looking or feeling overly bulky or cumbersome. This, coupled with its dedicated secure passport pocket, make this third-gen sling incredibly conducive to travel, allowing it to serve as a suitable alternative to a backpack for shorter trips, and making it especially ideal to use as a compact carry-on personal item when flying.

Comprising the majority of the sling’s three liters of storage space, the Day Sling 3’s main compartment opens to reveal two full-length pocket slips, a pair of elasticized mesh pockets for housing cables, cords, chargers, and other tech essentials, and a secondary zippered-pocket that also spans the sling’s entire length. The main compartment is also supplemented via a padded, quick-access front pocket with a key leash, and a third, hidden, rear-facing pocket for stashing passports and other important items that require a little extra security.

All in all, we were genuinely impressed with Aer’s Day Sling 3, from its modern, cutting-edge materials to clever design layout — it actually managed to convert one of our sling-skeptical staffers into a regular sling bag user. With that said, however, the pack isn’t without a few very minor issues. The main gripe we had with the sling was its FIDLOCK buckle. If the bag is worn upsidedown, the buckle will disconnect itself from the shoulder strap as soon as it’s placed on the wearer’s body. After only a day or two, this problem went away once we knew how to properly wear and orient the bag, though we can still see this happening if you’re in a hurry — like, say, rushing through the airport to catch your connecting flight.

On top of adding a few style points, the main idea of a sling is to offer a more compact and streamlined alternative to carrying around a full-sized backpack, and in this regard, Aer has knocked it out of the park. This is made all the more impressive considering that Aer has managed to engineer a sling that genuinely lends itself to travel. The Day Sling 3 provides enough organization and storage space to replace a backpack, with its three liters affording more than enough real estate to accommodate a wallet, smartphone, charger, keys, hand sanitizer, notebook, passport, sunglasses, headphones, and any other travel or EDC items that don’t necessitate a full-size backpack — but are still too bulky to carry in one’s pant pockets.

And, just like with Aer’s full-sized backpacks, it’s abundantly clear how much real-world knowledge and firsthand travel experience have gone into the Day Sling 3’s design. Not only does the sling sport a bevy of legitimately useful organizers, but features such as its custom zipper pull, waterproof zips, reinforced grab handle, and multiple hanging loops all point to just how thoroughly calculated of a bag the Day Sling 3 truly is.

Purchase: $79+

The 15 Best Sling Bags For Everyday Carry

Curious to see how Aer’s slings stack up against the competition? Then be sure to check out our feature guide to the best sling bags for everyday carry for a handpicked list of more than a dozen of the finest crossbody bags that money can currently buy.