⟲ 360° — drag meThe facts.
| Type | Thermal mid layer, windblock |
|---|---|
| Shell | Double-knitted wind-blocking shell with Leatt Warm Yarn |
| Material | 70% polyester, 20% nylon, 10% elastane |
| Seat | 4-way stretch ripstop reinforcement |
| Sun protection | UPF 50+ |
| Pockets | 1 chest pocket with concealed YKK zip |
| Protection class | None (not a protective garment) |
| Weight | 680 g |
| Warranty | 5 years (Leatt) |
| Colour | Stealth Black/Grey |
DescriptionThe whole story▼
Cold air finds its way through every gap in a riding jacket, and the Leatt ADV 3.5 ThermaFlow is designed to stop it close to your body. This thin, flexible mid layer uses a double-knitted, wind-blocking shell made with Leatt Warm Yarn, so it adds warmth without the bulk of a fleece. It slips under an adventure jacket on the bike and works as a light jacket at camp or in town.
The Stealth Black/Grey version is plain black, which makes it easy to combine with any riding outfit.
Key Features
- Double-knitted wind-blocking shell made with Leatt Warm Yarn
- Thin insulation layer that fits under adventure jackets
- Reinforced seat area in lightweight 4-way stretch ripstop
- Slimline stretch forearms to reduce bulk inside the jacket sleeve
- Overlocked seams for comfort on long rides
- UPF 50+ rated, Bluesign approved materials
- Concealed YKK chest pocket with low-profile puller
Warmth Without Bulk
The ThermaFlow 3.5 relies on its knit structure for insulation. The double-knitted outer blocks wind while remaining breathable, so heat stays in but moisture from your body can still move outward. At around 680 g it is a light addition to your luggage, and it packs down more easily than a padded jacket.
Designed as a Riding Layer
Details show that this jacket was made to be worn under protective gear. The forearms are slim and stretchy so they do not bunch inside the sleeves of a touring jacket. The chest pocket has a concealed YKK zip with a low-profile puller, which means no hard tab pressing against your chest under an outer layer. The seat is reinforced with 4-way stretch ripstop, because that is where the jacket meets the saddle.
Materials and Sustainability
The fabric blend is 70% polyester, 20% nylon and 10% elastane. Leatt states that the jacket uses Bluesign approved materials and meets the latest USA PFAS standard. A UPF 50+ rating gives sun protection when you wear it on its own at high altitude or on bright days.
Everyday Details
Overlocked seams help prevent chafing on long days in the saddle. A YKK main zip, reflective visibility details and a garment hanging loop complete the jacket. Leatt includes a 5-year warranty and ships it in plastic-free packaging.
Where It Fits in Your Kit
Think of the 3.5 ThermaFlow as the layer between a base layer and your riding jacket. On a cool morning it adds wind protection under a ventilated adventure jacket; at a fuel stop or campsite it becomes your outer jacket. Sizes run from S to 4XL.
What you should know
The ADV 3.5 ThermaFlow is an insulation layer, not protective motorcycle clothing. It carries no EN 17092 certification and has no protectors, so it should always be worn under a certified jacket when riding. It has no waterproof membrane either. For more warmth and a water-repellent finish, Leatt offers the ADV 5.5 ThermaFlow with graphene insulation.
Colour
Stealth Black/Grey is solid black with only a small grey label on the chest pocket and thin reflective lines on the back. The understated look works under any ADV jacket colour and as a casual jacket off the bike. Black also hides dust and the marks that backpack straps can leave.
Size guide
| Size | US | EU |
|---|---|---|
| S | 38 | 48 |
| M | 40 | 50 |
| L | 42 | 52 |
| XL | 44 | 54 |
| XXL | 46 | 56 |
| 3XL | 48 | 58 |
| 4XL | 50 | 60 |
Specifications
| Type | Thermal mid layer, windblock |
| Shell | Double-knitted wind-blocking shell with Leatt Warm Yarn |
| Material | 70% polyester, 20% nylon, 10% elastane |
| Seat | 4-way stretch ripstop reinforcement |
| Sun protection | UPF 50+ |
| Pockets | 1 chest pocket with concealed YKK zip |
| Protection class | None (not a protective garment) |
| Weight | 680 g |
| Warranty | 5 years (Leatt) |
| Colour | Stealth Black/Grey |
What's includedEverything in the box▼
- 1x jacket
Questions, one topic at a time.
Get the real shipping cost for this item to your address — the same rates as checkout.
Choose a destination and hit Estimate — we fetch the live rates for this item.
We’re based in Germany. Standard delivery goes by DHL and national postal services and takes about 2–5 days within Germany, 1–2 weeks within the EU and 2–6 weeks outside the EU. Need it sooner? Express delivery reaches most of the world within a few days — just choose it at checkout where available.
Your exact shipping cost is calculated by destination and weight and shown at checkout before you pay — no hidden fees. Express delivery is selectable at checkout where available.
Yes, we ship to over 130 countries. Prices, taxes and delivery times for your destination are calculated automatically at checkout.
Within the EU, no — our prices already include all duties and EU VAT. For deliveries outside the EU (e.g. Switzerland, the UK or the USA), your order may be subject to import duties and taxes set by your country. These are collected by the carrier when your parcel arrives, aren’t included in our prices, and are outside our control.
As soon as your parcel ships we email you a tracking link, so you can follow it all the way to your door.
On out-of-stock items you can request a delivery time or leave your email to be notified the moment it returns — just use the notification box on the product.
You have the right to cancel within 14 days of receiving your order. Register your return by email first; once it’s approved you have a further 14 days to send the goods back. Items should be unused and in their original packaging.
Register your return by email with your order number before sending anything back, and we’ll send you the return instructions. Please note: returns that aren’t registered in advance can’t be accepted.
The quickest way is to place a new order for the size you need and register a return for the original by email — just let us know it’s an exchange.
We’re sorry — that shouldn’t happen. Contact us with your order number and a photo as soon as you can, and we’ll arrange a replacement or refund right away. Faulty goods are always covered by your statutory warranty.
Refunds go back to your original payment method, usually within 3–5 working days of your return reaching our warehouse.
PayPal, all major credit and debit cards (Visa, Mastercard, American Express), Klarna (pay later and instalments), Apple Pay, Google Pay and more — all processed securely via PayPal and Mollie.
Yes. Choose Klarna at checkout to split your purchase into flexible monthly installments.
Your payment is taken when you place your order. If you choose Klarna, you pay later according to Klarna’s terms.
Every payment runs over an SSL-encrypted connection through certified providers. We never see or store your full card details.
If your order hasn’t shipped yet, contact us as soon as possible and we’ll do our best to change or cancel it.
No — you can check out as a guest. An account simply lets you track orders and reorder faster.
For customers in the EU, prices are shown including your country’s local VAT. For customers outside the EU, prices are shown without VAT — instead, your country’s import taxes and duties may apply on delivery (see the customs question).
Yes. Your invoice is attached to your order confirmation email and is also available in your account.
Yes. We’re an authorised dealer, so every product is 100% original and comes with the full manufacturer warranty.
Yes. Everything we sell is genuine and comes with the manufacturer’s warranty, on top of your statutory rights. Keep your invoice as proof of purchase and contact us if you ever need to make a claim — we’ll help you through it.
Our team is happy to help. Use the contact button below and we’ll personally help you choose the right gear or part.
Measure your head circumference about one centimetre above your eyebrows and compare it with the size chart on this page. Between sizes? Choose the smaller one — the padding beds in with use.
Yes — it’s tested and approved to the current ECE 22.06 standard and road-legal across the EU.
Most of our touring and sport helmets are Pinlock-ready and many include the insert. Check the ‘What’s in the box’ section on this page for this model.
Yes — the cheek pads are channelled so the arms of your glasses slide in comfortably.
Take out the washable lining and hand-wash it in lukewarm water. Clean the shell and visor with a soft cloth and water only — never solvents.
Our team will personally help you choose the right gear or part — around 24h for a reply.