Cybex Sirona S SensorSafe 2.1
The Sirona S Sensorsafe is packed with every safety feature you want in a convertible car seat. You actually install the car seat through the BASE so you don't need to reinstall it when you turn the child around. You will also find the same linear side impact protection as are on all Cybex car seats.
The included Sensorsafe clip adds extra peace of mind, by alerting you when your child is still buckled in, is too hot or cold, etc.