Alfa Romeo Tonale Owner's Handbook Manual page 121

In Europe the characteristics of child restraint systems are governed by regulation ECE-R44, which divides them into five weight
groups.
The ECE-R44 standard has been paired with the ECE R-129 regulation, which defines the characteristics of the new i-Size child
restraint systems (see the "Suitability of passenger seats for i-Size child restraint system use" paragraph).
Group
Group 0
Group 0+
Group 1
Group 2
Group 3
All restraint devices must bear the type-approval data, together with the control mark, on a label solidly fixed to the child restraint
system which must never be removed.
Age
Indicatively up to 9 months
Indicatively up to 2 years
Indicatively from 8 months to 4
years
Indicatively from 3 to 7 years
Indicatively from 6 to 12 years
Weight groups
up to 10 kg in weight
up to 13 kg in weight
9 - 18 kg
15 - 25 kg
22 - 36 kg
Size class / Fixing
ISO/L1
ISO/L2
ISO/R1
ISO/R1
ISO/R2
ISO/R3
ISO/R2
ISO/R3
ISO/F2
ISO/F2X
ISO/F3
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