CYBEX Platinum

Sirona T i-Size

Awarded a “Good” rating in the ADAC test, the Sirona T i-Size rear-facing car seat features all-round air ventilation. Choose the Plus option for an integrated sun canopy. Only compatible with the Base T or Base Z2.

Age 0 - 4 yrs
Weight max. 18 kg
Regulation UN R129/03

45 - 105 cm
76 - 105 cm

CYBEX Sirona T i-Size - Nautical Blue (Plus) in Nautical Blue (Plus) large image number 1 Small

CYBEX Sirona T i-Size - Nautical Blue (Plus) in Nautical Blue (Plus) large image number 2 Small

CYBEX Sirona T i-Size - Nautical Blue (Plus) in Nautical Blue (Plus) large image number 3 Small

CYBEX Sirona T i-Size - Nautical Blue (Plus) in Nautical Blue (Plus) large image number 4 Small

CYBEX Sirona T i-Size - Nautical Blue (Plus) in Nautical Blue (Plus) large image number 5 Small

CYBEX Sirona T i-Size - Nautical Blue (Plus) in Nautical Blue (Plus) large image number 6 Small

Test Winner 10/2023

CYBEX Sirona T i-Size - Nautical Blue (Plus) in Nautical Blue (Plus) large image number 1

CYBEX Sirona T i-Size - Nautical Blue (Plus) in Nautical Blue (Plus) large image number 2

Image shows the combination of several products, sold separately.

CYBEX Sirona T i-Size - Nautical Blue (Plus) in Nautical Blue (Plus) large image number 3

Image shows the combination of several products, sold separately.

CYBEX Sirona T i-Size - Nautical Blue (Plus) in Nautical Blue (Plus) large image number 4

CYBEX Sirona T i-Size - Nautical Blue (Plus) in Nautical Blue (Plus) large image number 5

Image shows the combination of several products, sold separately.

CYBEX Sirona T i-Size - Nautical Blue (Plus) in Nautical Blue (Plus) large image number 6

Image shows the combination of several products, sold separately.

Color: Nautical Blue (Plus)

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Features
Installation
Dimensions
What's included
Downloads
FAQ

Product Details

Product Code: 523000399 (Nautical Blue (Plus))

Specifications:

Age range: From birth up to 4 years
Child height: 45 - 105 cm
Child weight: Max. 18 kg
Approval regulation: UN R129/03

Travelling in Safety & Comfort ‒ Rear & forward-facing

Enjoy the ultimate travel experience with the CYBEX Sirona T i-Size rear-facing car seat. Your child can enjoy the height of comfort with features like all-round air ventilation promising pleasant temperatures in all seasons. Smooth 360° Rotation lets you get them on and off-board effortlessly, and helps you switch between rear or forward-facing travel. Recline the seat with one hand, for extra comfort on the road. And you can enjoy peace of mind through safety features such as integrated Linear Side-impact Protection. Get ready for blissful trips with your child, with the Sirona T i-Size.

Care instructions:

Fabric covers machine washable at 30° C

Compatible with:

Base T
Base Z2
Base Z*
Car Seat Cup Holder
Sirona T Line Summer Cover
SensorSafe 4-in-1 Kit Toddler
ISOFIX Guides

Installation with base: Pay attention to the i-size logo. If a vehicle seat is marked with this logo, it is suitable for use with all i-size child seats and therefore will not appear in our list of compatible vehicles. If your vehicle does not have an i-Size seat, please check the compatibility of your vehicle. If your vehicle is not displayed, please contact our customer service team.

*Please note that the Sirona T i-Size may have limited recline functionality when used with the Base Z.

Up to 50% higher safety: The Sirona T i-Size is a rear-facing car seat providing superior accident protection, reducing the risk of head or neck injury and improving safety by 50% (compared with the same seat forward-facing; results of testing using 2022 ADAC criteria). In a crash, the child is pushed towards the seat shell, where forces are distributed and lose impact. Rear-facing is mandatory for at least 15 months (76 cm tall). After that you are able to rotate the Sirona T-Size forward-facing, although, we recommend rear-facing travel for up to four years if possible.

Optimal breathability: All-round air ventilation provides year-round comfort. And the Plus fabric version has even better airflow, with a 3D mesh that increases breathability up to six times (compared to conventional fabric). The Plus line also features a sun canopy with mesh inserts to keep your child cool and protected.

Easy on and off-boarding: Get your child in and out of the car with ease. 360° rotation lets you swivel the Sirona T i-Size smoothly towards the car door with one hand, for easy boarding and less back strain. Rear-facing is mandatory for at least the first 15 months (up to a height of 76 cm). Then you can keep your child rear-facing or turn them forwards for extra comfort.

Show More Features

Comfort throughout their journey: The Sirona T i-Size features...

25% more side-impact protection: A proven Linear Side-impact Protection...

Grows with your child: The Sirona T i-Size evolves with your...

Good fit for the youngest travelers: A newborn inlay provides a ...

Stress-free boarding: Magnets let you attatch the...

Intuitive installation and anchorage: A secure base for the Sirona T...

Reliable UPF50+ protection: A UPF50+ sun canopy gives...

Installation

Base T

The Sirona T i-Size clicks on and off the Base T. This is installed using a load leg and ISOFIX. The Base T ensures safety and stability, and it can also be used with the Cloud T i-Size infant car seat. Look for the i-Size logo in your vehicle to check compatibility. If there is no i-Size logo but your car has ISOFIX, please check our Car Compatibility tool.

Dimensions

editorial-content-specification-title

Length: 715 mm

Width: 430 mm

Height: 680 mm

Weight: 15 kg

What's included?

What is included?

Sirona T i-Size toddler car seat
Sun canopy (included with plus line only)
Newborn Inlay
User guide

Downloads

FAQ

General

Can I use this car seat on a flight?

No, this car seat is not approved for use on an airplane.

Is it ok to keep using a car seat after an accident?

We at CYBEX strongly recommend that you replace a car seat after any kind of accident. This is because tiny hairline cracks, which may not be visible to the naked eye, can appear in the plastic parts of a car seat after an accident. These cracks can pose an increased risk to safety.

My car seat is faulty, how can I get it repaired?

Please refer to the retailer where you bought your CYBEX car seat. They will deal with the matter on your behalf.

Where can I get replacement parts for my product?

You can order replacement parts from a specialist retailer near you. To find a store near you, simply go to the Store Locator on the CYBEX Website.

When should I remove the newborn inlay?

The newborn inlay has to be removed when your infant reaches a height of 61 cm (corresponding to approximately 3 months). This ensures that your growing baby has enough space in the car seat.

How do I correctly secure my child in the seat?

Please observe the instructions in the User Guide. Adjust the child car seat to the size of your child and make sure that he or she is properly strapped in to ensure maximum safety.

When I remove the base from the vehicle it emits a warning signal. How can I stop this noise?

When the load leg is adjusted the base will emit a warning signal indicating that it is not correctly installed. If you want to remove the base from the vehicle, first push the load leg upwards to its uppermost position by pushing the adjustment button. Then fold the load leg back for storage within the base. The warning signal will stop when the load leg is fully folded back and in the designated area. If the base is not to be used for a long period of time the battery should be removed to avoid potential damage caused by leaking fluids.

My child keeps trying to wriggle out of the harness system. What can I do about this?

As a general rule, you can secure your child in the safest possible way if you follow these instructions: The impact shield should be positioned so it fits snug against the body without causing discomfort. The impact shield can also be adjusted in depth for a comfortable fit on the majority of models. You can tell that the impact shield is in the correct position if it is fully aligned with your child's body. Thick clothing prevents the harness/vehicle belt or impact shield from fitting tight to the body. Only a correctly adjusted restraint system can offer maximum protection. For this reason, your child should wear thin, close-fitting clothing. Thick clothing such as winter jackets and clothing with hoods (hoodies, teddy suits, etc.) as well as hats should be avoided. Once your child has been positioned in the seat, he or she can be covered with a blanket for warmth.

When am I allowed to use the Sirona's forward-facing position?

Once the child exceeds 15 months of age and has reached a minimum size of 76 cm you are allowed to use the forward-facing position of your Sirona car seat. This is not a must. We rather recommend transporting children in the Sirona's rear-facing position for as long as possible. The car seat allows rear-facing travel up to a height of 105 cm (approx. 4 years).

Can I wash the newborn inlay and cover of the car seat in the washing machine?

Yes, both are washable. Note however, that the foam in the newborn inlay needs to be removed before washing. It can be pulled out via slots in the fabric. You can put the foam back through the slots after the newborn inlay is washed and dried. We recommend using a delicate wash cycle and a maximum temperature of 30 degrees Celsius. Detailed instructions can be also found in the User Guide.

Installation and Securing your child

Can I install a rear-facing seat on the front passenger seat?

Rear-facing car seats must only be installed on the passenger seat if the front airbag has been deactivated. Placing your child on a passenger seat with an activated airbag poses an enormous risk of injury, and we at CYBEX strictly advise against this. For other types of car seats check the user manuals of both your car seat and your vehicle to find out if you should deactivate the airbag. Statistics show that the safest place for a car seat is on the rear seat behind the front passenger seat. Side airbags do not put your child’s safety at risk. If you have no choice other than to use the front passenger seat, please ensure that the seat is pushed back as far as possible and that the airbag is deactivated.

How should the headrest be adjusted?

Only a headrest adjusted to the optimum height will give your child the best possible protection and comfort. The height can be adjusted to various positions. The headrest must be adjusted so there is no more than 2 cm between the child’s shoulders and the bottom of the headrest.

Can I use the car seat on laterally-facing vehicle seats?

It is not permitted to use the car seat on laterally-facing vehicle seats.

Can I use the car seat on rear-facing vehicle benches (e.g. in vans or minibuses)?

No. This car seat cannot be used on rear-facing vehicle benches.

What do I have to bear in mind when installing the Sirona in my vehicle?

First, select an appropriate vehicle seat. Unfold the load leg until it locks with an audible CLICK. Release the buttons of the ISOFIX locking arms and push them out of the base to their furthest extent. Insert the arms into the ISOFIX anchorage points (make sure they lock with an audible CLICK and that the safety indicators show green). Push the base towards the backrest of the vehicle seat until it is fully aligned with the backrest. Moving the whole car seat back and forth, and from side to side will further brace it against the backrest. Always make sure that the load leg is extended completely (pull out the load leg by pushing the adjustment button until it touches the vehicle floor). Pull the leg out and into the next locking position (make sure the load leg indicator on the base shows green).

Can I also use this seat in a car without ISOFIX anchorage points?

No, this seat can only be installed in vehicles with ISOFIX anchorage points, due to the fact that it must be installed with ISOFIX in every position.

What should I bear in mind when installing the car seat in my vehicle?

Before purchasing the car seat, it is important to check if it is approved to be used in your vehicle. If your vehicle has an i-Size seating position compatibility is given. If you have no i-Size seating position, please scan the dedicated QR-Code on your "Quick Start Guide" or use the specific weblink provided on the Packaging Box, to access the Car Compatibility Tool of your product. For proper protection of your child, it is essential to use and install the car seat according to the instructions given in the User Guide. It can be downloaded via the CYBEX Website.

Safe Travel

Can I use the car seat even when the side airbag is activated?

Yes, the side airbag can remain activated when using the car seat.

Are both side-impact protectors (L.S.P.s) needed?

The Linear Side-impact Protection (L.S.P.) reduces the forces of a side-impact collision and thus also the risk of injury. Generally, we advise parents to install or fold out the L.S.P. on both sides of the car seat. However, if there is insufficient space for the L.S.P. nearest the middle of the vehicle, it is not absolutely essential. For safety reasons, please ensure that the L.S.P. nearest the door is always installed or folded out.

Is my child allowed to rest his/her legs on the rebound bar?

Relatively tall infants may rest their legs on the rebound bar. Bending the legs at the knee does not affect safety in any way. As long as the child has sufficient legroom you can use the seat in a rear-facing position.

The car seat is approved in compliance with the i-Size standard (UN R129). What does this mean?

i-Size is a European standard for car seats. Among other regulations i-Size states that infants must travel in a rear-facing position before the child's age exceeds 15 months and that, for the first time, side-impact protection is tested. To find out more about i-Size, check our Safety page on the CYBEX Website.

Usage

What kind of clothing should my child wear when seated in the car seat?

Thick clothing prevents the harness/vehicle belt or impact shield from lying tight against the body of the child. Only a correctly adjusted restraint system can offer maximum protection. For this reason, your child should wear everyday clothing. Thick clothing such as winter jackets and clothing with hoods (e.g. hoodies) as well as hats should be avoided where possible. Once your child has been positioned in the car seat, he/she can be covered with an extra blanket for warmth.

How do I know when my child needs to change to the next car seat?

We generally advise against switching to the next car seat prematurely. Even if your child’s feet protrude outside the car seat, your child has not necessarily grown out of the seat. However, if your child's head is protruding above the top edge of the highest headrest position, is taller than 105 cm, or weighs over 18 kg, it is time to change the car seat as it no longer affords sufficient protection to the vulnerable neck and head area. After changing the car seat, your child’s head should be positioned within the protective area of the height-adjustable headrest. If the new car seat has an impact shield, your child should be able to comfortably see over it. If your child disappears behind the impact shield, then he/she is definitely too small for the seat.

When is a child too big for the Sirona?

The Sirona can be used by infants between 45 cm and 105 cm in height or up to a maximum bodyweight of 18 kg (approx. 4 years).

Functionality

How do I install the cup holder?

On either side of the car seat there are little openings in the fabric of the seat cover indicated by stitching. If you look inside either of these openings you will see a grooved area in the car seat shell which the cup holder can be slotted into.