LEATT All Mtn 4.0
Tested in 2026
Adult
Mountain bike open-face
Score
64.2
out of 100
Star rating
3/5 Stars
Price
$
$
$
$
over $270
Performance
Specifications
Performance
Each metric is weighted differently based on crash severity. Scores combine to create the overall 100-point rating.
Helmet coverage
5.6
/ 6
Retention system strength
1.5
/ 6
Head protection in low-speed impact
7.6
/ 12
Angular head impact protection
19.8
/ 32
Head protection from concentrated impact
8.0
/ 8
Head protection in higher-speed impact
10.4
/ 12
Head protection variability in higher-speed impact
0.0
/ 2
Head protection variability in low-speed impact
0.3
/ 2
Helmet stability in a crash
4.5
/ 6
Head protection in standard-speed impact
6.4
/ 12
Head protection variability in standard-speed impact
0.0
/ 2
Total
64.2
/ 100
Specifications
Model
All Mtn 4.0
Brand
LEATT
Size
S, M and L
Helmet Type
Mountain bike open-face
Weight (Average from 3 sizes)
485g
Shell/Liner material
EPS & EPO
AIMS
YES
AIMS Type
360 Turbine
Retention System
Fidlock
Price Range
$$$$ (over $270)
Certification standard(s)
CPSC, ASTM, EN1078
