Supair RADICAL 4 – Ultralight Hike & Fly Harness

The Supair RADICAL 4 is the pioneer hike & fly harness, now in its fourth generation – light, flexible and made for the mountains. The harness alone weighs just 920 g in size M. Add the optional airbag-backpack module and it becomes a lightweight reversible harness with airbag protection and an integrated reserve container.

Light and compact, easy to set up and use, the RADICAL 4 adapts to your movements so you can play freely with the air – going fast, high and far. Its designer, Yoann Chavanne, describes “a feeling of smooth control”: the harness deforms slightly to follow the pilot’s body, giving soft, precise handling.

RADICAL 4 at a glance

• Type: ultralight open harness for hike & fly, ski flying and mountain flying
• Level: novice to experienced pilots, occasional or regular flying
• Weight: harness 910–970 g (S–L); with airbag module 2.16–2.26 kg
• Sizes: S, M, L – pilots from 160 to 205 cm (5’3″–6’9″)
• Options: harness only, harness + airbag-backpack module, or the module on its own
• Reserve: integrated container for 2.9–5.3 L reserves (in the airbag module)
• Colors: Petrol or Gold
• Certification: EN 1651 (harness alone); LTF with the airbag module

Choose your setup

• Harness only – the lightest option for hike & fly and ski flying when every gram counts. No seat plate – just ergonomic, semi-rigid leg straps.
• Harness + airbag-backpack module – zip on the module and the RADICAL 4 becomes a reversible harness with a pre-shaped airbag, an under-seat reserve container and a backpack for the walk up.
• Airbag module only – already own a RADICAL 4? Add the module whenever you want.

Watch the RADICAL 4

Understanding your RADICAL 4

Ultralight and flexible

The RADICAL 4 has no seat plate. Semi-rigid, ergonomic leg straps with independent Mylar stiffening support you in a seated position, and a foam-stiffened back adds comfort. The result is a harness that packs tiny and moves with you.

The airbag-backpack module

The optional module attaches with a zip. It adds a pre-shaped airbag, an integrated reserve container under the seat and turns the RADICAL 4 into a reversible backpack (62 L in S/M, 67 L in L) – one bag for the hike and the flight.

Features

• Self-stabilizing leg straps
• Pre-equipped for a reserve: shoulder rescue straps and riser sheath
• Speed bar pulleys, pole holder and removable waist belt
• About 10 L back pocket, hydration hose passage and vario mount on the right shoulder
• Adjustable chest strap width, backrest angle and shoulder length
• Edelrid Pure Slider carabiners included

Frequently asked questions

Do I need the airbag module?

The harness alone is EN certified and is the lightest option for experienced pilots and ski flying. For extra passive safety, an integrated reserve container and a backpack, choose the harness with the airbag-backpack module (LTF certified).

Which size should I choose?

S fits 160–175 cm (5’3″–5’9″), M fits 170–185 cm (5’7″–6’1″) and L fits 180–205 cm (5’11″–6’9″). Check the weight ranges in the Specifications tab, or ask us:  WhatsApp · ✉️ Email · 📞 (917) 359-6449

Which reserve fits?

Reserves from 2.9 to 5.3 L, in the container integrated into the airbag module.

RADICAL 4 or ALTIRANDO LITE 2?

The RADICAL 4 is lighter and more minimalist, with leg straps instead of a seat plate. The ALTIRANDO LITE 2 is a reversible harness with a seat plate and airbag as standard – more comfort for longer flights.

Can I return or exchange the RADICAL 4?

Harnesses are final sale, but you can exchange your RADICAL 4 for a different size. Ask for our free expert advice before you order:  WhatsApp · ✉️ Email · 📞 (917) 359-6449. See the Shipping & Returns tab for details.

How long does delivery take?

Supair usually has the RADICAL 4 in stock. We order yours as soon as your order is confirmed: import and customs clearance take 4–6 business days to reach our US warehouse, then 1–2 business days handling and 3–5 business days standard delivery. Expedited orders are usually processed the same day – choose UPS Next Day Air at checkout. Tight deadline?  WhatsApp · ✉️ Email · 📞 (917) 359-6449