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Thermal Zephyr Runner Jacket

£135 Sale price
Unit price  per 

Thermal Zephyr Runner Jacket

M's Thermal Zephyr Runner Jacket

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free shipping over £50
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Regular fit, Size Chart William is 6'1" and wears size M

With nylon ripstop and a water repellent finish, the Janji Thermal Zephyr Runner Jacket provides nearly weightless warmth in a small, easily stowable package for chilly trail adventures.Read more

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Nearly weightless warmth

Super compressible PrimaLoft® Gold Active insulation packs a ton of breathable warmth — ideal for high-output movement — in an ultra-packable design

Bungee toggles

Bungee toggles allow the hemline to be cinched down in extra cold or windy conditions

Ergonomic sleeves

Streamlined sleeves with semi-elastic cuffs stay in place in motion



Weightless feel
Ultra-light ripstop shell sheds light rain and snow with a PFC-free DWR finish for more eco-friendly weather protection

Targeted insulation
The Thermal Zephyr uses the lightest active insulation that exists to cover the areas where you need the most warmth while allowing for greater breathability + heat release where you don’t

Hold it down
Chest snap under zipper allows for adaptable venting

Better warmth
PrimaLoft® Gold Active Insulation with 45% recycled content provides more sustainable warmth on colder days

Lock it down
Minimal semi-elastic cuffs protect against the weather while allowing room for gloves or mittens

Designed for the trail
Dropped back hemline acts as a splatter guard to keep you warm and dry on messy trail adventures and bungee toggles at the hem cinch the jacket down for extra wind protection

Stay seen
Signature reflective logo on front and “watermark” reflectivity on back increases visibility in low light

materials + specs

Zephyr Runner
100% nylon ripstop (38gsm) w/ PFC-free DWR

Targeted insulation
PrimaLoft® Gold Active Insulation — 45% PCR (post consumer recycled) content, 55% polyester fill

169g / 5.9oz (M’s Medium)

Garment made in Vietnam


The Thermal Zephyr Runner uses PrimaLoft® Gold Active Insulation with 45% recycled content for more sustainable warmth on colder days. The shell features PFC-free DWR finish for more eco-friendly weather protection.

Our Zephyr Runner fabric is also bluesign® certified meaning it is free from harmful chemicals and is fabricated in a way that meets a high environmental standard.

Learn more about our sustainable initiatives here.

Customer Reviews

Based on 15 reviews
Don from SW England
Soft, comfortable and stylish

I run commute so this is a second layer on chilly mornings, which gets stowed away compactly in my rucksack in the afternoons. As with other Janji products, the pocket you need is right there!
Only downside is that the zipper pulls have frayed. I must have washed them too aggessively.
Love the button functionality that holds the garment around the torso when the zipper is undone. Looks like running with a cape!

Doug McRobb
Cool, er, hot jacket

Bright, light and toasty, perfect jacket that packs down superbly.

Andres Ignacio Figueroa Labarcs
don´t go out without the jacket,

incredible jacket, one would think that it is very light to keep warm, but it is perfect, it became the jacket that I wear everywhere. in all situations, even on the bike in semi-cold situations.

plus: it is so small that it is impossible to go out without it.

I would love a version with a hat, for those even colder and windier situations.

Clement Herron

M's Thermal Zephyr Runner Jacket

Aaron Steely
Versatile, lightweight, perfect

Title says it. I wear this anywhere from 50 F down to 10F, haven’t tested lower. Difference is a merino long sleeve baselayer for cold weather or t shirt for warm.

It’s super lightweight and packable, perfect for my long runs in the mountains with a cold start (20F average winter start).

Dries fast, has a nifty chest button for venting when I get warm, too.

Love it all around ! 150 lbs, 5’10”, size medium is perfect


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