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Book a Baby Gear Consultation (click here) | Free Shipping $99+
Book a Baby Gear Consultation (click here) | Free Shipping $99+

Cybex Eternis S All-in-One Convertible Car Seat with SensorSafe

Save 20%
Original price $379.95
Current price $303.96

List Price:$303.96


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Ships in 1 - 3 weeks

Ships in 1 - 3 weeks


All-in-one car seats are the future of child transportation. Instead of purchasing three or more separate car seats for their little ones, more and more parents are investing in one car seat that will last their child the entire time they will be using a car seat. This long term solution acts as an infant car seat, convertible car seat, AND a booster seat! Designer baby brand Cybex now has the perfect all-in-one seat for your family: the Cybex Eternis S with SensorSafe!

Engineered for Safety

The Cybex Eternis S has been designed from the bottom up to give your precious passenger with the safest ride possible. Its steel reinforced frame provides a strong and stable base that can withstand the forces of a crash without cracking, snapping, or bending. The adjustable linear side impact protection (LSP) system absorbs up to 25% more impact forces from side impact collisions, and the patented 3-position reclining headrest keeps your child’s head from falling forward when they fall asleep which keeps their head and neck safely within the protection of the headrest.

Protection That Grows

Invest in the Cybex Eternis S’ advanced child safety protection features that will grow with your child for years to come. Your baby can start using the seat at just 4 pounds all the way until they are a whopping 120 pounds! The car seat can be rear-facing up to 50 pounds and forward facing with the harness up to 65 pounds. Once you remove the five-point harness your big kid can continue to use it as a booster seat until they graduate from car seats altogether.

SensorSafe Compatible

The Cybex Eternis S is compatible with the revolutionary SensorSafe app which connects your child’s car seat to your smartphone giving you peace of mind that they are always safe and secure in their seat. The included SensorSafe buckle provides essential alerts to help prevent critical situations: when your child unbuckles the clip while the car is moving, if your child is put at risk of vehicular heatstroke because of ambient temperature changes or from being left alone in the car, and if your child has been seated for too long.


  • Magnetic Buckle Holders
  • SensorSafe Technology Included
  • Steel Reinforced Frame
  • Linear Side Impact Protection System
  • 3-Position Reclining Headrest
  • 12-Position Adjustable Headrest
  • No-Rethread 5-Point Harness


  • Weight Limits:
    • Rear Facing: 4-50 lbs
    • Forward Facing with Harness: 22-65 lbs
    • Forward Facing as Belt Positioning Booster: 65-120 lbs

Shipping Policy

  • In stock items are shipped via UPS Ground from our warehouse in Boston, MA within 1-2 business days after placed. Transit time is 1-5 business days once it has been shipped.

  • Items listed as shipped from manufacturer take an additional 1-2 business days for processing but most orders ship within 3 business days. You will receive tracking information as soon as we receive it from the manufacturer. Transit time is generally 1-5 business days once it has been shipped.

  • We offer free shipping on orders over $99 within the continental US.

  • Our full shipping policy, including transit times can be viewed here.


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