Some child restraint systems span several ECE groups (European child safety standard), classified by the weight of the child. They have the ability to transform into a higher class, allowing them to grow with the child. The usual combinations are between Groups 0+ and I, and Groups I and II/III.

Group 0+/I seats are usually rear-facing seats. In this case, the child continues to face the rear, even after they have outgrown the infant carrier. This offers considerable safety benefits over forward-facing systems with integrated harnesses, as the child’s neck is not normally strong enough to support the head in an accident. Modern rear-facing seats, like the CYBEX Sirona, are designed with a 360° rotation system that gives it the ability to face forward when the child is too old to be facing the rear.

Today, we will take a closer look at the second type of combination seats for children from 9 kg or approx. 9 months:

 Group I/II/III (9 – 36 kg, approx. 9 months to 12 years)

Parents can save buying another seat by investing in a Group I/II/III child car seat. From the age of about 12 months, when the child has outgrown the infant carrier, these seats can be used right up to the age of 12 years.


Babies and toddlers should be transported rear-facing for as long as possible. Doctors and accident researchers even recommend that children remain in rear-facing child seats until the age of 4. These child seats work like a protective shield protecting the sensitive head and neck area and reducing the risk of injury in a frontal collision. A baby’s head is equal to 25% of its overall body weight and the neck muscles and spine are still not fully developed. There is no need to move your child to a Group I seat or Group I/II/III combination seat if their feet are poking out of the bottom of the infant carrier or the child can sit up. However, if the head protrudes above the edge of the carrier and the baby weighs more than 13 kg, you should change seats immediately, as the most vulnerable part of the child’s body is not protected.

In each growth and development stage the child changes in height and shape, therefore it is important that the combination child seat has the necessary ability to adapt to your child’s body dimensions guaranteeing best safety and perfect fit.

When in Group I mode (9-18 kg, approx. 9 months to 4 years) CYBEX combination child car seats feature an adjustable safety cushion which perfectly adapts to the growth of the child. The safety cushion can be adjusted forwards and backwards, offering enhanced safety and comfort compared to conventional 5-point harness systems. This system resembles an inflated airbag and helps to significantly reduce the force of impact in the event of an accident. The force is distributed over the safety cushion and absorbed by its impact-absorbing materials. The harness does not injure the child, while at the same time the risk of dangerous injuries of the cervical vertebrae is reduced, as the child’s head is not abruptly thrown forward and backward.

Child car seats featuring a safety cushion (impact shield) have achieved best ratings on a regular basis in the child restraint system tests conducted by German Stiftung Warentest and ADAC having the lead in the respective groups. Having compared the test results for the period from 2007 to 2012, we found that the Top 3 in Group I are car seats with a safety cushion (impact shield). The Top 10 of Group I/II/III is clearly dominated by safety cushion (impact shield) systems: 9 out of 10 are child car seats with safety cushion (impact shield) systems with excellent results with respect to collision safety.

With the height-adjustable headrest and the removable seat insert, the car seat itself adjusts for the perfect fit and maximum safety. The head and shoulder protectors of the enhanced L.S.P. System Plus provides for best side-impact protection in every growth stage.


For children aged approx. 3 and above (15 kg) the combination car seat can be easily converted from Group I into a Group II/III seat.

In the case of Group II/III child restraint systems, children are generally secured using the vehicle’s own retractable 3-point safety belt. Children should never be secured with just a pelvic belt. In the event of a collision, the child’s upper body would be propelled forward and the child could sustain serious injuries to the head. The optimal features of a Group II/III seat include a comfortable booster seat with a height-adjustable backrest and sufficient shoulder protection in case of a side-impact collision.

The CYBEX Pallas model range (Group I/II/III, 9-36 kg, approx. 9 months to 12 years) and the CYBEX Solution series (Group II/III, 15-36 kg, approx. 3 – 12 years) both offer a special head protection for a high level of safety while asleep. The patented 3-position reclining headrest shifts the balance point of the child’s head slightly back, prevents it from falling forward and keeps the child in the safety zone while asleep.

It is important to ensure that the switch to a Group II/III child restraint system is not made too early. A small child can easily slip out of the safety belt, particularly when it falls asleep en route. The child’s shoulders are also too narrow to hold the safety belt securely in place. In this case it is highly recommendable to secure the child with the safety cushion in Group I.


The idea behind a child restraint system is to adapt the car’s safety belt system to the size of the child. Standards ECE R 44/03 and 44/04 indicate that a booster seat for children weighing more than 15 kg is theoretically sufficient to fulfil this purpose. However, we strongly recommend using a complete seat with a backrest to offer optimum protection to the pelvis, shoulders and head. The differences between simple booster seats and sturdy seats with backrest and snugly fitting safety belts are astounding.

We discourage parents from opting for just a booster seat for the following reasons: The problem with booster seats is that they do not offer any side protection. A safety seat with a backrest is fitted with a side protection, preventing the child’s head from hitting the car window in a collision. Moreover, a side-impact collision is capable of causing serious injury, and children may also suffer additional injury from the side airbag. Airbags may protect adults, but they can pose a serious risk to children. Statistics show that one in four collisions involve impact to the side of the vehicle.

Even more alarming is the fact that these side-impact collisions account for 20 per cent of all collision-related deaths and seriously debilitating injuries among children. A booster seat does not provide sufficient protection to the child’s most vulnerable areas. There is always a danger that the booster seat could slide underneath the child. Booster seats do not position the safety belt around the shoulder area, causing the belt to sit too closely to the neck. The compact design of a seat with a backrest not only ensures that the child is secured more firmly but that the belt is also always in the right position.

For further information please visit our CYBEX Child Safety Centre:

This series of safety tips is going to be continued. So please stay tuned…