One base, three car seats and up to seven years of flexible family travel. The CYBEX Base S is the foundation of the new Platinum S-Line Modular System, connecting with the Cloud S infant carrier, Sirona S rotating toddler seat and Anoris S Airbag.

ISOFIX connectors, a height-adjustable load leg and central LED indicators help support a secure installation, while one-handed rotation turns the attached car seat towards the vehicle door for easier boarding. Shop the CYBEX Base S online at Chelsea Baby or visit our Midlands showroom for expert compatibility and installation advice.

One Base, Three CYBEX S-Line Car Seats

The CYBEX Base S has been designed to remain in the vehicle as your child progresses through the first stages of their car-seat journey.

Begin with the rear-facing Cloud S infant carrier from birth. When your baby is ready to leave their infant carrier, the same Base S gives you two different next-stage options: continue rear-facing with the Sirona S or choose forward-facing airbag protection with the Anoris S Airbag.

The CYBEX Base S is compatible with:

• CYBEX Cloud S
• CYBEX Sirona S
• CYBEX Anoris S Airbag

Compatibility is model-specific. Base S is not designed for Cloud T, Sirona T or other CYBEX car seats outside the S-Line system.

Choose Your Toddler-Seat Route

Base S gives families a genuine choice when their baby outgrows the Cloud S infant carrier.

The CYBEX Sirona S supports extended rear-facing travel up to 105 cm or 20 kg, approximately 4.5 years. It also provides one-handed 360-degree rotation and can be used forward-facing once the child is at least 15 months old and 76 cm tall.

The CYBEX Anoris S Airbag provides a forward-facing alternative from 76–125 cm and at least 15 months, up to a maximum child weight of 21 kg. Its full-body airbag is integrated into the adjustable impact shield, while Base S allows the seat to rotate 180 degrees towards the vehicle door.

Whichever route you choose, the existing Base S can remain installed in a compatible vehicle.

One-Handed Rotation for Easier Boarding

The Base S rotation mechanism turns each compatible car seat towards the open vehicle door, reducing awkward lifting and leaning when placing a child into the seat.

Rotation depends on the attached model:

• Cloud S rotates 180 degrees towards the vehicle door.
• Sirona S rotates through 360 degrees.
• Anoris S Airbag rotates 180 degrees towards the vehicle door.

The rotation mechanism is operated with one hand, helping parents position the seat while supporting their child. Always return the car seat to its approved travelling position and check the relevant indicator before beginning the journey.

Central LED Installation Indicators

The Base S includes an onboard safety assistant with central LED indicators designed to provide clear installation feedback.

The display shows the status of the ISOFIX connectors, supporting load leg and attached car seat. When the Anoris S Airbag is fitted, the system also communicates the status of the impact shield and airbag battery.

The indicators provide a useful visual check, but they do not replace the installation instructions. Parents should still follow the Base S and car-seat user guides and check each connection before travelling.

ISOFIX and Height-Adjustable Load Leg

The CYBEX Base S attaches to compatible vehicle ISOFIX anchorage points. Colour-coded controls and installation indicators are designed to make the connection easier to understand and verify.

A height-adjustable load leg extends to the vehicle floor, providing an additional point of contact and helping reduce movement of the base. The foot of the load leg must sit firmly on an approved section of the vehicle floor as shown in the product and vehicle instructions.

Vehicles with floor-storage compartments may have specific restrictions regarding load-leg installation. Check the vehicle handbook and CYBEX compatibility information before purchasing.

Base S cannot be installed using the vehicle seat belt and should only be used in an approved vehicle seating position with suitable ISOFIX anchorage points.

Easy Transition Between Car Seats

When your baby outgrows the Cloud S, the infant carrier can be removed from the base and replaced with either Sirona S or Anoris S Airbag.

This removes the need to purchase and install another base when progressing to the next stage. It may also make the transition easier for families using more than one compatible S-Line seat over several years.

The Base S adapter required to connect Cloud S is included with the base. Keep all supplied parts and the user guide in a safe place so they remain available when changing between seats.

What Is Included With the CYBEX Base S?

The standard Base S package includes:

• CYBEX Base S
• Base S adapter for Cloud S
• Batteries
• Quick-start guide and access to the digital user guide

The Cloud S, Sirona S and Anoris S Airbag are separate products unless the listing is specifically described as a bundle.

Always check the individual product description before purchasing to confirm exactly which components are included.

CYBEX Base S vs Base T

Base S replaces Base T as the foundation of the new CYBEX Platinum modular car-seat range.

The most significant improvement is the wider choice available at the toddler stage. Base T is associated with the outgoing Cloud T and Sirona T system. Base S works with Cloud S and allows parents to choose either the rear-facing Sirona S or forward-facing Anoris S Airbag.

Base S also introduces centralised feedback for the Anoris S impact shield and airbag battery when that seat is attached.

The main Base S improvements include:

• Compatibility with three S-Line car seats
• A choice of rear-facing or airbag toddler seats
• Potential use from birth to approximately seven years
• Central LED installation indicators
• Anoris S impact-shield and battery-status feedback
• One-handed rotation with every compatible seat
• Updated S-Line modular compatibility

Base S and Base T are separate systems. Cloud S, Sirona S and Anoris S Airbag are not listed as compatible with Base T, while T-Line seats should not be installed on Base S.

If you already own a CYBEX base, check its exact model name before purchasing a new car seat. Similar-looking CYBEX bases are not automatically interchangeable.

Does the CYBEX Solution S Use Base S?

No. Solution S is a high-back booster for children from 100–150 cm and does not attach to Base S.

Once a child has outgrown Sirona S or Anoris S Airbag, Solution S installs directly in the vehicle. Its integrated ISOFIX connectors provide stability, while the child is secured using the vehicle’s three-point seat belt.

The Base S modular journey therefore covers the Cloud S and one of the two S-Line toddler seats. Solution S completes the wider S-Line range but uses its own installation system.