Sonia
it is the insert that came with the car seat, but I can't leave it in because the straps are coming from below her shoulders with it in and the car seat says you can only use the bottom two holes on rear facing.
The straps already have those padding things on them but she can turn her head and lay into the side of the seat a bit more than she could before.
What brand is the car seat u have? i rang IGC Dorel (the manufacturer of most department store carseats) and they said u can move the insert up to the next hole. u can use all 4 holes but need to move the insert up. it is same with my new carseat. we now have a cargo amazon and it goes up to 12 kg rearfacing and is made by hipod. most safensound ones go up to 12 kg rearfacing.