Lightweight jacket with excellent ventilation and useful features

Product Overview

Overall rating:

Score 7

Leatt AllMtn Jacket 4.0 V22


  • Great ventilation, good breathability, magnetic hood system


  • Arm fit is tight, jacket tail could be longer


Leatt AllMtn Jacket 4.0 V22 review


Price as reviewed:


South African brand Leatt forged its reputation in the protection game, but has recently added an extensive range of feature-packed riding kit. The new Leatt AllMtn 4.0 jacket is no exception, and has a range of unique features – but are they enough to make the cut on our list of the best mountain bike jackets


Detail photo showing chest area of a grey and sand coloured jacket, showing a zip and chest closure

The strap on the chest means you can run the jacket open without it flapping about


It’s cut from a thick and durable four-way stretch softshell fabric that is cut closer to the body than most. The material is rated at 10,000mm waterproof and 10,000g/m2 breathable, which are reasonable – OK for light rain rather than sustained downpours.


Leatt’s unique features include a magnetic hood system and a ‘Climb Vent Connector’. The first sees a small magnet (included) you can attach to the top of your helmet to ‘lock’ the hood in position (and stop wind from flapping it back off the helmet). There’s also a second magnet built into the jacket behind the neck to keep the hood from swinging side to side when it’s not being used. It works too – especially the one for when the hood is down.

Detail photo of the back of a hood on a grey jacket showing pull cord

The hood is adjustable, and uses magnets to hold it in place

The Climb Vent describes a chest fastening that stops the jacket flapping fully open when riding with it unzipped while climbing to help airflow. It also works, but I’d rather have my jacket fully open when climbing at slow speeds to maximise ventilation rather than reduce any minor flapping.

Zipped chest and side hand warmer pockets manage storage, there’s a lift pass pocket on the left arm – like you’d find on a ski jacket – and stretchy cuffs and hem with extra grippers to stop it riding up at the back and help keep the very tailored fit snug against the elements.


Talking about fit, the first thing I noticed are very slim sleeves and tighter shoulders compared to the ‘regular’ width and length in the main body. Three different riders wore this jacket and all commented on this. So, despite the 360-degree stretchy material, the arms feel a bit tight and restrictive. I also found the huge, tall collar annoying when riding with it open at the neck; it basically flaps around against the face.

Photo detail of the sleeve of a waterproof jacket showing the word 'Leatt'

The sleeves of the Leatt jacket were cut surprisingly tight

In the field

Leatt’s fabric isn’t rated exceptionally highly on paper, for waterproofness or breathability,  but ventilation is actually pretty good – there’s no boil-in-the-bag sensation and during a heavy downpour while shooting, the exterior beaded well and stayed dry for hours. There’s an effective vent behind the shoulders, but sweat can still build up in the tighter arms when you’re working hard.


I’ve been impressed with most new Leatt kit I’ve tested, but not so much this time – the price is decent and the huge hood covers an all-mountain helmet properly and the magnet system does help calm down any flapping when riding fast, but ultimately the quirky cut and slightly stiff feel to the jacket let it down, and the tail could also do with extending a bit lower at the back to help with spray coming up off the rear tyre.


Weight: 582g (L)
Sizes:XS, S, M, L, XL , XXL, XXXL
Colours:Black, Dune (tested), Rust