POLAR + AUSTRAL
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THE UPGRADE

79 €Save 19 € vs two belts

One buckle, two straps. Switch your style in a click.

4.8·Based on 22 verified reviews

Free worldwide shipping, always. No minimum order. Every order is tracked.

1Your belt · Choose your first route
POLAR

The shortcut over the pole. The belt that goes with everything.

2Your second strap · Choose your second route
AUSTRAL

Red earth below. Blue sky above. Wear the distance.

Both straps share the same buckle. The two widths cannot be mixed — choose the same width for both.

Choose your width

Not sure? Go Slim. It fits everything.

Free shipping30-day returnsLifetime guaranteeSecure paymentPouch included

One buckle. Two straps. Every style.

The Upgrade gives you one buckle and two interchangeable straps in different colors. Keep the same buckle and switch straps depending on the outfit, the mood, or the destination. The mechanism is the same as on board: slide, pull, done. Two routes, one belt.

The Upgrade · strap
Logbook entries

What customers are saying

4.8/ 5

Based on 22 verified reviews

Featured

Given to my boss for his retirement

30 years at Air France. He picked the Transatlantic and the Runway — the first flight he ever captained (CDG-JFK) and the runway he landed on for his last flight. He tightened the buckle at his farewell drinks and got teary. Thank you.

Translated from French

Claire B.· On The Upgrade · slim· December 2025

Wish the pouch was bigger

Belt is everything I hoped. One minor thing: the small cotton pouch only fits one strap at a time. For travel, I end up tossing the spare strap in my Dopp kit. A dual-pocket pouch would have been a nice touch at this price.

Noah B.· On The Upgrade · authentic· September 2025

Slight delay on delivery

Ordered mid-February, arrived March 3rd — a week later than the banner promised. No stress, belt is top quality and support replied within a day when I asked. Just adjust expectations vs. the delivery estimate.

Emma T.· On The Upgrade · authentic· March 2022

Great concept, took a minute

Beautiful product. I'll admit the first swap of the strap confused me for a minute — there's a small lip on the buckle you have to tilt up. Once you get it, two seconds. Father's Day delivery was on time.

Michael P.· On The Upgrade · authentic· June 2019

Love it, instructions could be clearer

Took me a good 5 minutes to figure out the strap swap the first time. Once you get it, 10 seconds. A tiny diagram in the box would have saved me the head-scratching. Otherwise: buckle is gorgeous, colors are true, shipping was quick.

Daniel F.· On The Upgrade · slim· February 2019

Father's Day gift, he loved it

Dad's a retired Delta pilot. I got him navy and black straps with one buckle. He sent me a selfie at Sunday brunch wearing it. First time in 10 years he liked one of my presents.

Kate R.· On The Upgrade · slim· June 2017

Two belts, one buckle, genius

The modular system is the real upgrade (pun intended). I can do black on weekdays and red on weekends with the same hardware. Swap takes 15 seconds. Worth every euro.

Tom B.· On The Upgrade · authentic· November 2015

From chinos to dress trousers without a second thought

Brown Silk Road on beige chinos during the week, blue Transatlantic on dress trousers in the evening. One buckle, two straps, and the belt becomes two belts. I live in Florence, I wear it for work and for dinners out — practical and never dull. Free worldwide shipping, arrived in four days.

Translated from Italian

Matteo C.· On The Upgrade · slim· April 2026

Green and grey cover almost everything

Two colors, two moods. I wear the green with linen shirts and jeans, the grey under a blazer. The same buckle holds both — and makes the swap feel more like a ritual than a chore. Smartest accessory I've bought this year.

Translated from Dutch

Thomas R.· On The Upgrade · slim· April 2026

Green and grey cover almost everything

Two colors, two moods. I wear the green with linen shirts and jeans, the grey under a blazer. The same buckle holds both straps — and makes swapping more of a ritual than a hassle. Smartest accessory I've bought this year.

Translated from Polish

Michał G.· On The Upgrade · slim· March 2026

Green and grey cover almost everything

Two colors, two moods. I wear the green with linen shirts and jeans, the grey under a blazer. The same buckle holds both — and makes the swap feel more like a ritual than a chore. Smartest accessory I've bought this year.

Translated from German

Philipp N.· On The Upgrade · slim· March 2026

Two straps, one buckle, genius system

Black Polar for the office during the week, red Austral for weekends and aperitifs. Same mechanism, two completely different styles. Strap swap in ten seconds. I travel a lot for work and I carry just one buckle with two straps rolled up in my suitcase — saves space. Recommended.

Translated from Italian

Giulia B.· On The Upgrade · authentic· February 2026

Brown for summer, black for winter

One buckle, two straps. The brown one with linen shirts and light chinos, the black under the wool suit. Swapping takes under ten seconds. That's how you should think about everything in your wardrobe — less stuff, more wear.

Translated from Polish

Tomasz R.· On The Upgrade · authentic· June 2025

Brown for summer, black for winter

One buckle, two straps. The brown with linen shirts and light chinos, the black under a wool suit. The swap takes under ten seconds. More things in a wardrobe should be thought about this way — less stuff, more use.

Translated from Dutch

Jeroen K.· On The Upgrade · authentic· June 2025

Brown for the day, black for the evening

Architect, weddings on weekends, meetings on Monday. The brown one with chinos and a linen shirt; the black one under a dark suit. Same buckle, two lives — and swapping takes two seconds. Worth every cent.

Translated from Portuguese

Tiago F.· On The Upgrade · authentic· May 2025

Brown for summer, black for winter

One buckle, two straps. The brown with linen and light chinos, the black with a wool suit. The swap takes under ten seconds. More things in a wardrobe should be thought about this way — less stuff, more use.

Translated from German

Jonas F.· On The Upgrade · authentic· March 2025

Two straps, one buckle, brilliant idea

The brown strap on the beige chino during the week, the black one on jeans on the weekend. Swap takes ten seconds. Saves money, saves wardrobe space, and it’s always the same buckle. I recommend it to every traveler friend I have.

Translated from Spanish

Mateo F.· On The Upgrade · slim· September 2024

Birthday gift to myself

I treated myself to the Upgrade for my 40th. Brown strap for summer, black one for autumn. Haven't touched my old belts in three months.

Translated from French

Raphaël D.· On The Upgrade · slim· August 2024

The interchangeable strap system is really well thought-out

Gave this to my dad for Father's Day. A black Polar and a red Austral strap on one buckle. He was skeptical for 30 seconds, then he got it and went to change twice in the same morning to try both. Simple concept, perfect execution.

Translated from French

Julien D.· On The Upgrade · authentic· June 2024

The concept sold me, no regrets

I was skeptical at first — why pay more for two straps when one belt is enough. But one buckle, two colors depending on the day, is genuinely useful. The Silk Road brown and the Amazonas green, I swap from chinos to jeans without a second thought.

Translated from French

Karim F.· On The Upgrade · slim· November 2022

Two straps, one buckle, sold

The green one for the weekend, the orange one for evenings. Same mechanism, two moods. I hesitated between The Belt and The Upgrade for months — zero regrets picking the duo.

Translated from French

Xavier L.· On The Upgrade · authentic· November 2020

The concept multiplies the belt

Since I understood that one buckle = two straps, I think differently about accessory purchases. Very clever. The brown and the black cover me for summer and winter with a single mechanism.

Translated from French

Mélanie V.· On The Upgrade · authentic· October 2016

Why The Upgrade.

Two colors. One buckle.

The buckle is shared between both straps. Switch in seconds, exactly like on board. The aluminum buckle is built to last through both.

Every combination is yours.

Every color in the collection is available for both straps. Choose any two. Every pairing says something. Make it count.

Adjusts exactly like on board.

Slide the strap through the buckle and pull to tighten. Fits any waist size up to 110 cm continuously.

Built to fit every trouser.

Two widths. Slim (38mm) fits all standard belt loops including dress trousers, chinos and slim jeans. Authentic (48mm) is the exact on-board format, for jeans and cargo pants. Both straps must be the same width — the buckle is shared.

Born in Paris. Built on one obsession.

Fly-Belts was founded in Paris in 2012. The obsession: take the most iconic piece of aviation design and make it genuinely wearable. Not as a novelty. Not as a gadget. As a real belt, built to last, worn every day. Wear the plane.

The perfect gift.

Two colors make it personal and thoughtful. Ships in a fabric pouch inspired by business class amenity kits — ready to give, no wrapping needed.

In your parcel

What's included. On its way to you.

1 aluminum buckle
Shared between both straps
2 straps
Two colors, same width
Fabric pouch
Business class · gift-ready
Free shipping
Tracked · worldwide
Shipping

Free worldwide shipping on every order, with no minimum. Every order is tracked. France and Europe: 3 to 5 business days. International: 7 to 14 business days.

Returns

Returns and exchanges are accepted within 30 days of delivery, provided the belt is in new and unworn condition. Return shipping costs are at the buyer's expense. Wrong width? Wrong models? Contact us and we sort it out.

Warranty · lifetime

Lifetime guarantee on the buckle

Buckle guaranteed for life. The same hardware as in commercial airliners, redesigned for your waist. If it ever fails, we replace it.

Full terms

Specifications

AuthenticSlim
Width48mm38mm
Max waist110 cm110 cm
BuckleAluminum (×1, shared)Aluminum (×1, shared)
StrapsHigh-resistance woven nylon (×2)High-resistance woven nylon (×2)
Compatible withJeans, cargo pants, wide loopsAll standard belt loops
Includes2 straps + 1 buckle + pouch2 straps + 1 buckle + pouch

Both straps must be the same width. The buckle is shared.

Questions about The Upgrade.

How does the strap swap work?
Release the buckle from the first strap, clip it onto the second. Two gestures. The same buckle, a different route.
Can I mix an Authentic strap with a Slim strap?
No. Both straps must be the same width. The buckle is designed for one width at a time and cannot be shared across the two formats.
Can I choose two straps in the same color?
Yes, though most people choose two different colors to get the most out of the combination.
Will this fit my trousers?
If you choose Slim (38mm), yes. The Slim fits all standard belt loops including dress trousers, chinos, slim jeans, and most jeans. If you wear mostly jeans and cargo pants, choose Authentic (48mm).
Is the buckle really from an airplane?
The buckle reproduces the exact design of commercial airline seatbelt hardware, manufactured to the same specifications. It is cast in aluminum rather than steel to keep it light and comfortable for everyday wear.
How do I clean the straps?
Wipe with a damp cloth or hand wash in cold water with mild soap. Air dry flat. Do not machine wash.
Read all FAQs

Take it further.

The Belt

The Belt

1 complete belt 1 color of your choice

One belt. One color. One destination.

49 €Free shipping
Add to cart
The First

Three belts · One box

The First

3 complete belts 3 colors of your choice

Three belts. Three routes. More colors, more options, one order.

109 €Free shipping
Get The First