Britax Kidfix i-Size High Back Booster

  • £199.00
    Unit price per 
Tax included.

ISOfix High Back Booster Seat
Suitable from 100-150cm
Approximately 4 to 12 years


The new generation KIDFIX i-SIZE has been developed in partnership with leading car manufacturers, to give the ultimate car travel safety to your child. It's equipped with the proven technologies of XP-PAD* and SecureGuard** for frontal impact protection, whilst the new design SICT protects your child from side collisions. Carefully placed air ventilation holes aid air circulation to keep your child comfortable for longer.

*To protect your child's sensitive neck area in case of a frontal impact, Britax-Römer has developed a shock-absorbing foam pad. It prevents the impact of your child's chin on their chest, absorbing up to 30%  of the energy. A jerky forward head movement is reduced and the neck is protected. At the same time it provides additional padding around the edges of the seat belt.
**The SecureGuard helps to protect your child’s delicate abdominal area by adding an extra – a 4th – contact point to the 3-point seat belt. By keeping the lap belt in an optimal position over your child’s pelvic bones SecureGuard helps reduce abdominal forces in the event of a frontal collision by up to 35 % and at the same time allows your child freedom of movement during the journey.

Our SICT offers superior protection to your child in the event of a side collision. It reduces impact forces by minimising the distance between the car and the car seat and deforms to absorb the energy before it reaches your little one. To benefit from the protection, simply adapt the SICT on the side of the car seat closest to the door. SICT reduces the side impact forces by up to 40%.


Britax-Römer are excited to announce that our KIDFIX i-SIZE is the winner of the latest ADAC crash-tests with the score of 1.8 in the 100 - 150 cm category! ADAC describes the KIDFIX i-SIZE as "the best car seat for big kids".
The results are made up of the following factors:
safety, handling, comfort, and hazardous substances.

The ADAC test result is a score out of 5. The closer that mark is to 0, the better the score. All aspects of the car seat are tested: its safety in case of frontal or lateral impact, its ease of use, the comfort of the child and whether harmful substances are present in the car seat.

'The strengths of KIDFIX i-SIZE include low risk in injury in frontal impact, very low risk of injury in a side impact, very little harmful substances, stable installation, and easy installation with low risk of misuse. KIDFIX i-SIZE is also lightweight and comfortable for both children and adults to use. Britax Römer has once again proven its capability to develop and produce some of the safest and most user-friendly car seats. The result specifically shows that the seat has been developed with safety in mind.

We’ve only used 100% recycled polyester in the making of the fabric covers for GREEN SENSE. Up to 138 plastic PET bottles per product* have been turned into soft yarn which are then spun to create premium fabric covers.
*Atlantic Green only


Dimensions H63 – 83 x W48 x D42 cm
Weight 6.7 kg

Meets the ECE R129 regulation