
Convertible seat height markers have been introduced with the 2010 australian standard. THe 2013 australian standard introduced new shoulder height markers for extended rear facing and extended harnessing.
Convertible car seats can include extended rear facing (A4) car seats, which allow child to travel in rear facing mode for an extended period of time (till approximately average of 30 months.)
Once again understanding what the height markers mean is key to ensuring your child is in the correct car seat for their age and height.Ignore what you think is the correct information to keep your child rear facing; follow the instructions on the shoulder height markers.
A2 Convertible Car seat Height Markers

The upper shoulder height markers indicate the maximum shoulder height for a child in the restraint. When the child’s shoulder is at the top marker they are ready to move to the next type of restraint.
The lower shoulder height marker indicates the minimum shoulder height for a child before they can be turned around to a forward facing position. If the child’s shoulder is below the marker they should remain rear facing.
For an A2 convertible child restraint this marker is a minimum of 35 cm
A4 Height Markers
Th A4 child restraint was introduced in 2013 Australian Standard, which was finally approved on 17 September 2014. The A4 Car seat is a car seat which has three shoulder height markers; the lowest marker indicates that you can turn your child forward facing; however you can leave your child rear facing until they reach the middle shoulder height marker.
Maxi Cosi Height Markers
The highest Rear Facing Shoulder height markers should be at 39 cms. However there are some car seat manufacturers which do not have the second should height marker for rear facing at 39 cm, these being the Maxi Cosi Euro and Maxi Cosi Hera which have the second marker at only 37 cm.
This 2 cm difference would mean you would need to turn your child at an earlier age than manufacturers which have a marker height of 39 cm (i.e. Infa Secure and Britax)
It should also be noted here that Maxi Cosi needed to recall their original A4 car seats as they were not certified by SAI Global.
Convertible car seats
Convertible Car Seat (0-4) descending order by tallest rear-facing marker
- (A4 Category) Safe n Sound Meridian SICT/ Platinum SICT/Platinum SICT Isofix:RWD facing: ??? FWD facing: ???
- (Pre-2014) Safe n Sound Meridian SICT/ Platinum SICT: RWD facing: 36-37cms. FWD facing: 43-44cm
- Safe n Sound Compaq AHR: RWD facing: 36cm. FWD facing 44cm
- Infasecure Kompressor/Neon/Glider/Ascent/Cosi Compact/Trident: RWD facing to: 34-36cms. FWD facing to: 41.5-43cm
- Safe n Sound Compaq/Meridian/Haven: RWD facing to: 34-35cms. FWD facing to: 43cms.
- Hipod Milan: RWD facing to: 33cm. FWD facing to: 43cm
- Hipod Cairo: RWD facing to: 33cm. FWD facing to: 42cm
- Maxi Cosi Hera: RWD facing to: 33cms. FWD facing to: 41cms
- Cargo Hybrid: RWD facing to: 32cm. FWD facing to: 42cm
- Mother’s Choice Emperor: RWD facing to: 32cm. FWD facing to: 40cm
- Babylove Cosmic: RWD facing to: 31cms. FWD facing to: 41cms
- Safety 1st Sentinel: RWD facing to: 30cms. FWD facing to: 38cms.