What Are i-Size Car Seats? : i-Size car seats are part of the latest European car seat safety regulation (UN R129), designed to offer enhanced protection and ease of use for parents and children. Unlike traditional car seat groupings based on weight, i-Size car seats classify suitability by your child’s height, providing a more accurate fit and improved safety performance. These seats are rigorously tested for side-impact protection and must be installed using ISOFIX, reducing the risk of incorrect fitting. With rear-facing travel required up to 15 months minimum, i-Size car seats help keep little ones safer for longer. Whether you’re looking for a 360 swivel seat or a rotating infant carrier, i-Size ensures your car seat meets the highest modern safety standards.