CYBEX Base S 360° Rotating ISOFIX Car Seat Base

CYBEX Base S Modular Rotating ISOFIX Base for S-Line Car Seats

The CYBEX Base S is the only car seat base you’ll ever need. Designed as the foundation of the new Platinum S-Line modular system, it replaces the Base T. This rotating ISOFIX base stays in your car from your baby’s very first journey until around 7 years old, taking three different S-Line car seats as your child grows. Approved to UN R129/04, it’s built for busy families who want a quick, confident installation every time.

Three seats, one base

The Base S works with the CYBEX Cloud S Rotating Baby Car Seat from birth up to approx. 24 months, then with the CYBEX Sirona S Rotating Toddler Car Seat for extended rear-facing travel up to 4.5 years, or the CYBEX Anoris S Airbag Car Seat. Because the base stays put, moving up to the next seat is simple, and you can go back to the Cloud S for your next baby. If you’re starting from day one, the CYBEX Cloud S Baby Car Seat with Base S Rotating Base gives you both in one box.

One-handed rotation

Smooth, single-handed rotation turns the seat towards the car door: 180° with the Cloud S and Anoris S Airbag, and a full 360° with the Sirona S. Side entry means no awkward twisting or lifting over the door frame, making it easier to position your child and tighten the harness correctly, especially when you’re juggling a baby and bags.

LED safety indicators

A car seat can only protect your child if it’s fitted correctly. The Base S has an onboard safety assistant with LED indicators that show the status of the ISOFIX connectors, load leg, impact shield and battery. One glance tells you everything is set up properly before you drive off.

Fast, secure ISOFIX installation

ISOFIX connectors and a height-adjustable load leg create a rigid, stable connection to your car and reduce movement in a collision. Colour-coded ISOFIX release buttons and clear indicators guide you through a reliable setup in minutes.

Made to last

Built from durable materials with smart engineering, the Base S is designed for years of daily use and more than one child, making it a long-term investment in your family’s safety. As the UK’s extended rear-facing specialists, we’ll always help you keep your child rear-facing for as long as possible with the best advice.

Please note: the Base S is designed exclusively for S-Line seats and is not compatible with any T-Line car seats, such as the Cloud T or Sirona T. The CYBEX Sirona Si Rotating Toddler Car Seat and CYBEX Anoris Si Airbag Car Seat each have an integrated ISOFIX base built in, so they don’t need a Base S.

Compare the Base S with the rest of our infant carrier car seats and bases, the wider CYBEX car seats line-up, or everything CYBEX at Little Peas. You can also browse all i-Size car seats, our baby car seats and our full car seats collection.

Want to see the S-Line in person? Visit our Dunfermline showroom to get a demonstration of the Base S and its compatible seats in your own car. To explore the full Platinum S-Line family, visit CYBEX.

CYBEX Base S Specifications