10-Year Car Seat The seamless transitions between modes offer up to 10 years of use from your Eternis S. An in-seat recline helps provide correct ergonomic positioning and extra legroom that lets your child ride rear-facing for longer.

SensorSafe The chest clip SensorSafe technology automatically syncs to the phone app to provide alerts if unsafe situations arise, including your child becoming unbuckled, the back seat being too warm or cold, or if the child is seated too long.

All-In-One Car Seat The CYBEX Eternis S is the only seat your child will need from birth and beyond. Featuring rear-facing, front-facing, and belt-positioning booster modes, the Eternis S is designed for use from birth up to 120 lbs.

Linear Side Impact Protection The Linear Side Impact Protection system (L.S.P.) absorbs up to 25% more impact forces in certain crashes when compared to the same car seat without L.S.P. extended.

Patented Reclining Headrest The Eternis S headrest helps prevent the child's head from falling forward while asleep, keeping the head and neck in a safe position. The headrest also features 12 height settings for easy adjustment as your child grows.

Converts to Booster Seat Ensure your child has an age-appropriate seat as they grow. Your Eternis S can be converted into a belt-positioning booster seat with a comfortable high back, suitable for children between 40 and 120 pounds.