i-Size and UN Regulation No. 129

Child Restraints I-Size UN Regulation No. 129
Last modified: Aug 05, 2026

i-Size and UN R129 are related but not interchangeable. UN Regulation 129 is the approval framework for Enhanced Child Restraint Systems; i-Size is one category within it.

What i-Size identifies

R129 also covers specific-vehicle ISOFIX, belted, booster-seat, and booster-cushion categories. i-Size restraints are primarily designed for compatible i-Size seating positions and prescribed anti-rotation arrangements. Approval labels and the vehicle manual establish compatibility. See Child Restraints and Seat Safety.

Sources

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