we have one type for ds but were having problems with him still getting out of it (its the 28asb) it has a steel buckle but he works his way out of it. the next option is to have another harness from them - cant remewmber number but it fastens all at the back of him into the car rather than the front! just thought i would ask here in case anyone by chance has one they dont use anymore. its the type for a challenging child - he has autism and is a houdini!! rather than the physical support type ones!
just thought worth asking on off chance! otherwise we will probably have to buy one, and then will be selling the one we have only had about 9 months!! he is only 3 but big for his age so has to be in a high back booster or a normal booster due to height and weight!