The Ideal Bag for Festival Lovers: The "UNDERTHESUN" Backpack

Founded in 1890 as a wholesale bag distributor, MIZUNO BAG Co., Ltd. now also manufactures OEMs and their own in-house products. The company has launched a festival-focused bag brand called UNDERTHESUN. They offer a lineup of products to fit different festival styles, beginning with their first model, the "TOTHECORE" backpack.

So why did Mizuno Bag, a long-standing bag maker, decide to focus on “festivals”? We spoke with Shota Ito, who is in charge of "UNDERTHESUN."

Wanting to Restore the Sense of "Connecting Through Music" Lost During the Pandemic

The concept of "UNDERTHESUN" is "making connections". When music festivals were being cancelled one after another in 2021 due to the pandemic, Ito’s desire to “bring back that feeling of people reconnecting under the sun after COVID through the joy of festivals and music” sparked the idea for the brand.

"Music festivals and music culture have always been a big part of my life, so I wanted to contribute in my own way, which led to founding the brand. The name is written as one word, without spaces, to express the idea of 'connection.'”

In 2022, the first product—the TOTHECORE—launched through the crowdfunding platform "Makuake," exceeding the funding goal by an impressive 1,453%.

Thoughtful Features in "TOTHECORE" for Enjoying Festivals

“The ‘TOTHECORE’ backpack was developed for urban festivals and took about half a year to make. We designed everything—from the choice of materials to the functional features—with two key ideas in mind: wanting everyone to enjoy music with peace of mind, and making a bag that I would genuinely want to use at a festival myself,” says Ito.

When it was initially released during the pandemic, the key concept was “antibacterial,” so they used a nylon material called “photocatalyst” that deactivates viruses in sunlight. Recently, however, in response to user requests, they have switched to water-repellent nylon so the bag can withstand rain at festivals.

The main pocket has a generous 30-liter capacity, perfect for enough items for a 2-day, 1-night trip. There’s also a drawstring compartment in the bottom. While it connects to the main compartment, this two-layered structure allows for direct access only from the bottom, so wet or muddy towels and clothes can be separated from the rest of your belongings for easy storage.

It’s clear the bag is packed with carefully considered details, but what was Ito most particular about?

“I focused especially on the number and arrangement of external pockets. For example, I like to wear my backpack on the front during live music. So, the flap pocket—where you most often reach—uses a double zipper that’s easy to open even in crowds, and the pocket opens wide like a gadget pouch.”

"Also, the side zipper that accesses the main compartment is angled so you can easily open and close it one-handed while wearing the backpack," Ito explains.

Another standout feature is the insulated side pocket.

"For me, enjoying a drink under the sun goes hand-in-hand with listening to music, so adding an insulated pocket was a must from the start. The pocket fits two 350ml cans vertically, and there are mesh sections for ice packs both above and below.

It was a technical challenge to create a cylindrical pocket, but through close work with the factory, we perfected the design," Ito recalls.

There are even features to reduce the burden of carrying the bag.

"Our company has years of experience in making Randoseru (Japanese school backpacks). We used that know-how to place thick, cushioned mesh pads on both the shoulder and lower back areas. This helps keep your spine straight and makes the bag feel lighter on your shoulders and back.

Plus, the gap created in the middle of the back panel improves ventilation. The bag also features a chest strap, so it stays firmly in place and comfortable to wear, even when you’re moving around actively."

"THESUN_FF" Series Developed for Outdoor Festivals

Following the "TOTHECORE," a new series called "THESUN_FF," designed for outdoor festivals prone to changing weather, was also released. The "ROOTS BR" is one of the products from this line.

"We developed this with Fuji Rock, the leading outdoor festival, in mind. However, at the time, I had never actually been to Fuji Rock, so I proceeded with production imagining 'going to Fuji Rock for the first time with a bag I made myself,' while also reflecting feedback from current Fuji Rock fans," says Ito.

The user surveys overwhelmingly requested "water resistance." To meet this demand, materials with 30,000 mm water pressure resistance and additional water repellency were used for the main body of the bag and the included rain cover to ensure no water gets in even under harsh conditions.

The shoulder straps feature zippered pockets for credit cards or earphones, as well as drawstring pockets to hold water bottles or smartphones.

To suit light camping as well, gear loops for attaching leisure sheets, folding chairs and more have been added, along with a large mesh pocket and bungee cords on the front to prevent items from shifting during use.

The "THESUN_FF" series has also launched sub-bags, such as the sacoche-type "INTHEAIR" and the multi-use "ROLLWITHIT" that can serve as both a bag-in-bag and a shoulder pouch.

"'INTHEAIR,' in particular, is a popular item. While it has a slim, minimalist design, it still offers enough storage for things like water bottles. Customization options, like adding festival wristbands to the D-ring on the shoulder strap or the gear loop on the front, are a hit with users," Ito shares.

No Other Bag Brand Is This Obsessed with Music Festivals

With both music festivals and their attendees becoming more diverse, we asked about the future of "UNDERTHESUN."

"For our products, I plan to continue incorporating the lessons I learn each festival season and the feedback from our customers. For example, this year there have been requests like 'I want a larger body bag,' so we're looking into the reasons behind this need and what kind of bag UNDERTHESUN could offer.

In any case, I believe there's no other bag brand as committed to music festivals as we are, so we'll continue to stay true to that. Through exhibiting at festivals and beyond, I hope to reach more music lovers and festival- and concert-goers. If UNDERTHESUN can inspire more people to experience truly 'awesome' live music, that would make me happy."

Developed with insights from Ito, a true festival fan himself, and communication with users at its core, UNDERTHESUN's products will surely keep evolving alongside changes in the festival scene.