1. Introducció
This user manual provides essential information for the safe and proper installation, use, and maintenance of your CYBEX Aton B2 i-Size Infant Car Seat with Base One. Please read this manual carefully before first use and keep it for future reference. Failure to follow these instructions may result in serious injury.
Safety Warning: Never leave your child unattended in the car. Installation of this child seat on the passenger seat with an activated front airbag is not permitted.
2. Producte acabatview
The CYBEX Aton B2 i-Size is a stable and high-quality infant car seat designed for children from birth up to approximately 24 months (max. 13 kg or 45 cm - 87 cm). It comes with the Base One ISOFIX for secure installation.
2.1 Components
- CYBEX Aton B2 i-Size Infant Car Seat
- Base One ISOFIX
- Inserció nounat
- XXL Sun Canopy

Image: The CYBEX Aton B2 i-Size infant car seat in Bay Blue, featuring its ergonomic design and integrated harness system.

Image: The Base One ISOFIX, showing its adjustable support leg and ISOFIX connectors for secure vehicle installation.
3. Configuració i instal·lació
3.1 Car Seat Preparation
Before placing your child in the car seat, ensure the newborn insert is correctly positioned for infants up to 60 cm. The insert provides optimal support and protection for smaller babies.
3.2 Base One ISOFIX Installation
The Base One provides a secure and stable foundation for the Aton B2 i-Size car seat using your vehicle's ISOFIX anchor points.
- Extend ISOFIX Connectors: Press the release buttons on the Base One to extend the ISOFIX connectors.
- Attach to Vehicle: Push the ISOFIX connectors onto the ISOFIX anchor points in your vehicle until they click into place. Green indicators will confirm correct engagement.
- Push Base Firmly: Push the base firmly against the vehicle seat back.
- Adjust Support Leg: Extend the support leg until it firmly touches the vehicle floor. A green indicator on the support leg will confirm correct positioning. Ensure the leg is stable and does not wobble.

Imatge: Frontal view of the Base One, highlighting the ISOFIX connectors and the adjustable support leg.

Image: The Aton B2 i-Size car seat securely attached to the Base One, demonstrating the combined unit's profile.
3.3 Car Seat Attachment to Base
- Place Car Seat: Position the Aton B2 i-Size car seat onto the installed Base One.
- Feu clic al lloc: Push the car seat down firmly until it clicks securely onto the base. A green indicator on the base will confirm correct attachment.
- Verifica la seguretat: Always check that the car seat is firmly attached to the base by pulling it upwards.
4. Instruccions de funcionament
4.1 Protegir el vostre fill/a
- Open Harness: Press the red button on the buckle to open the harness.
- Col·loca el nen/a: Col·loqueu el vostre fill al seient del cotxe.
- Fasten Harness: Bring the two buckle tongues together and insert them into the buckle until they click.
- Apretar l'arnès: Pull the central adjustment strap to tighten the harness until it fits snugly against your child's body. Ensure no slack.
4.2 Headrest and Harness Adjustment
The headrest and harness system adjust simultaneously in 11 positions to grow with your child, ensuring optimal safety and comfort.

Image: Illustration showing the vertical adjustment of the headrest and integrated harness system.
To adjust, locate the adjustment lever at the back of the headrest. Squeeze the lever and slide the headrest up or down to the desired height. Release the lever to lock it in place. The harness will automatically adjust with the headrest.
4.3 XXL Sun Canopy
The integrated XXL sun canopy provides excellent protection against sun (USF 50+) and wind. It can be easily extended or retracted.

Image: The car seat with its XXL sun canopy extended, demonstrating its protective coverage.
To extend the canopy, simply pull it forward. To retract, push it back into its housing.
4.4 Side-Impact Protection (L.S.P. System)
The integrated Linear Side-impact Protection (L.S.P. System) absorbs impact forces early, protecting your child in the event of a side collision.

Image: Close-up of the car seat's side, indicating the location and function of the Linear Side-impact Protection (L.S.P.) system.
4.5 Carrying Handle Positions
The carrying handle has multiple positions for transport and stability. Refer to the markings on the handle for correct usage.
5. Manteniment
5.1 Neteja
- Fundes de tela: The fabric covers are removable and machine washable at 30°C on a delicate cycle. Do not tumble dry, iron, or dry clean.
- Parts de plàstic: Netegeu les peces de plàstic amb anunciamp cloth and mild detergent. Do not use harsh cleaning agents or solvents.
- Sistema d'arnès: Netegeu les corretges de l'arnès amb anunciamp cloth. Do not remove or lubricate the harness buckle.
5.2 Emmagatzematge
When not in use, store the car seat and base in a clean, dry place away from direct sunlight and extreme temperatures. Ensure all components are dry before storage to prevent mold or mildew.
6. Solució De Problemes
| Problema | Causa possible | Solució |
|---|---|---|
| Car seat not clicking onto base. | Base not fully engaged with ISOFIX, or support leg not correctly positioned. | Ensure ISOFIX indicators are green and support leg indicator is green. Re-attach car seat firmly. |
| Harness is difficult to tighten/loosen. | Harness straps are twisted or obstructed. | Untwist straps. Ensure no clothing or debris is blocking the adjustment mechanism. |
| Green indicators not showing. | ISOFIX connectors or support leg not fully engaged. | Push ISOFIX connectors further until they click. Adjust support leg until it firmly touches the floor and locks. |
7. Especificacions tècniques
| Característica | Detall |
|---|---|
| Número de model | 521004437 |
| Dimensions (L x A x A) | 66 x 44 x 39-56.5 cm (Car Seat) |
| Weight (Car Seat) | 3.8 kg |
| Weight (Base One) | 3.65 kg |
| Edat recomanada | From birth to approx. 24 months |
| Pes màxim del nen | 13 kg |
| Child Height Range | 45 cm - 87 cm |
| Norma de seguretat | UN R129/06 (i-Size) |
| Tipus d'instal·lació | ISOFIX with support leg |
| Tipus d'arnès | Arnés de 3 punts |
| Posicions del reposacaps | 11 |
| Material principal | Plastic (Base), 100% Polyester (Exterior Fabric) |
8. Garantia i Suport
CYBEX products are manufactured with the highest quality standards. For information regarding warranty terms and conditions, please refer to the warranty card included with your product or visit the official CYBEX weblloc.
For technical support, spare parts, or any other inquiries, please contact your local CYBEX retailer or the customer service department. Keep your proof of purchase and product model number (521004437) ready when contacting support.





