Xtend, technically known as an impact shield, is a protective cushion that effectively operates as a child retention system. The easy to use accessory means that children of between 9 - 18Kgs (group 1) can safely travel in seats that are designed for group 2 or 3. Essentially, by adding the XTEND to either Montecarlo, Montecarlo Plus or Momo Plus Models , the car seat can then be used for children from 9 - 36Kgs in weight. FEATURES: By adding the XTEND to Montecarlo, Montecarlo Plus or Momo Plus, the car seats can be used for children from 9 - 36 Kg in weight, group 1, 2 & 3. Manufactured from Expanded Polystyrene, lightweight but also highly energy absorbent. Extra ventilation windows allows your child to feel comfortable and fresh while travelling.