The Britax Traveller Plus car seat is designed for children with special needs, and is suitable for children aged 4 years old to 11 years old. This car seat is easy to install using an adult seat belt and has a simple clip between the chest pads that prevents your child struggling out of the harness once strapped in there car seat. One of the features this car seat has is that it has an optional seat extension that makes the seat deeper and more comfortable for a bigger child.