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Visit our Showroom or Call us at 904-342-8648
Visit our Showroom or Call us at 904-342-8648

Eternis S with SensorSafe

Original price $379.95 - Original price $379.95
Original price
$379.95 - $379.95
Current price $379.95
Color: Lavastone Black


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The Eternis S All-In-One car seat offers three stages in one-easy to use car seat, suitable from 4 lbs. up to 120 lbs., or 57 inches tall. First used as a rear-facing infant seat up to 50 lbs., then as a forward facing convertible seat and lastly as a belt positioning high-back booster seat. With seamless transitions between modes, the Eternis S offers versatile protection that lasts all the way through your child’s first 10 years of age..

Eternis S Headrest


The 12-position, height-adjustable headrest of the Eternis S and Eternis S with SensorSafe offers comfortable protection as your child grows. The integrated no-rethread harness adjusts with the headrest movement so there’s no need to reconfigure the harness as your child moves up in the seat.

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Patented 3-position reclining headrest helps prevent the child's head from falling forward while asleep, keeping the head and neck in a safe position and ensures a comfortable sleeping position.

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The L.S.P. System of the Eternis S and Eternis S with SensorSafe extends on the door facing side of the installed car seat and offers increased safety during a side-impact collision. The L.S.P. System reduces the forces of an impact in the event of a side-impact collision by approximately 25% when compared to the same car seat without L.S.P. extended..

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The in-seat recline feature of the Eternis S adjusts to multiple positions, helping to provide a correct ergonomic positioning, a better fit, and extra legroom, allowing your child to safely ride rear-facing longer - up to 50 lbs. The seat comfortably angles the child to help minimize head slump and keep airway open, for a custom, cradled fit

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For easy installation and removal from the vehicle seat.

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removable cup holder can be positioned on either side and is dishwasher safe for easy clean up.

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The Eternis S is also available with SensorSafe Technology built into the chest clip. SensorSafe Technology provides essential alerts when unsafe conditions arise, like if a child unbuckles themselves while the vehicle is in motion; if the back seat has become too warm or too cold, if a child has been seated for too long, and if the driver accidentally leaves the child behind after the vehicle has been switched off. These alerts are provided through an installed vehicle receiver and a user-friendly smartphone SensorSafe App, which also provides guidance on installation, FAQ’s, a directly line to customer service and more. Select the Eternis S with SensorSafe for this additional safety feature.


Will this car seat fit my child?

The Eternis S is designed for children between 2.3 -54.4kg (4-120 lbs.) with a height between 43.2-144.8 cm (17-57 inches).

Will the Eternis S convertible car seat fit my vehicle?

CYBEX does fit checks on a variety of vehicles. Due to variations in make, models, and years of manufactured vehicles, it is encouraged to try the seat in your vehicle at a retail location nearest you. You should try both rear facing and forward facing modes and in different locations (outboard rear seat, vs middle seat). CYBEXCYBEX recommends getting your seat checked by a Certified Child Passenger Safety Technician. You can find this free service by visiting to find a seat check nearest you.

Does the Eternis S convertible car seat have an expiration?

Every car seat has an expiration due to Regulatory changes and technology enhancements in child passenger safety. The Eternis S convertible car seat has been certified for 10 years of use. Once your car seat has reached its expiration date, we recommend recycling the seat by contacting your local community recycling center.

How much does the Eternis S convertible car seat weigh?

The weight of the car seat (excluding the infant positioning pillow is 11.8 kg (26 lbs)

How big is the Eternis S convertible car seat?

The seat will vary in height and depth depending on the recline angle and headrest position. The seat with headrest down and in the upright position is 63.5 H x 51 W x 64.2 cm (25.5” H x 20” W x 25.3” D inches)