1. Product Overview
The tectake Sophie i-Size Car Seat is designed to provide both safety and comfort for your child during car journeys. It features a robust frame, an 8-step height-adjustable headrest, and a secure 5-point harness system. Approved according to ECE R129/03 standards, this car seat includes side impact protection and is suitable for children from 76 cm to 150 cm (approximately 15 months up to 36 kg).
Key features include:
- i-Size approval with side impact protection and ISOFIX installation.
- 8-step height-adjustable headrest for growing children.
- Robust and flexible 5-point harness system.
- Thick, comfortable padding for optimal support.
- Removable and machine-washable polyester cover for easy cleaning.

Image 1.1: The tectake i-Size Car Seat installed in a vehicle, demonstrating a child mannequin secured with the harness.
2. Safety Information
This car seat is approved under the ECE R129/03 (i-Size) standard, ensuring high safety performance. It features integrated side impact protection for enhanced safety in the event of a side collision. The robust 5-point harness system secures the child firmly, distributing forces evenly.
Important Safety Guidelines:
- Always read the full instruction manual before installation and use.
- Ensure the car seat is correctly installed and secured in the vehicle.
- Never leave your child unattended in the car seat.
- Do not use the car seat if it has been involved in an accident, even if there is no visible damage.
- Regularly check all straps, buckles, and adjustment mechanisms for wear or damage.
- Ensure the child is dressed appropriately to avoid overheating or interference with the harness.

Image 2.1: Overview of the car seat's safety and comfort features, highlighting i-Size approval and robust construction.
3. Setup and Installation
3.1. ISOFIX Installation (for children 76-100 cm)
For children between 76 cm and 100 cm, install the car seat facing forward using the ISOFIX connectors and the Top Tether. Ensure both ISOFIX indicators turn green and the Top Tether is correctly tensioned.
- Locate the ISOFIX anchor points in your vehicle.
- Extend the ISOFIX connectors from the car seat base.
- Push the ISOFIX connectors onto the vehicle's anchor points until they click into place and the indicators turn green.
- Push the car seat firmly against the vehicle's backrest to remove any slack.
- Attach the Top Tether strap to the designated anchor point in your vehicle and tighten it securely.

Image 3.1: Detail of the secure ISOFIX installation.
3.2. 3-Point Belt Installation (for children 100-150 cm)
For children between 100 cm and 150 cm, the car seat can be used as an i-Size booster seat, secured with the vehicle's 3-point seat belt. Guide the vehicle's seat belt through the designated guides on the car seat and ensure it is snug across the child's shoulder and lap.
- Place the car seat on the vehicle seat.
- Position your child in the car seat.
- Fasten the vehicle's 3-point seat belt around your child and the car seat.
- Ensure the lap belt passes under the armrests and across your child's hips.
- Ensure the diagonal shoulder belt passes through the red belt guide near the headrest and rests centrally on your child's shoulder, not on their neck or arm.
3.3. Headrest Adjustment
The headrest is 8-step height-adjustable. Adjust it so that the shoulder straps are at or slightly above your child's shoulders when using the 5-point harness, or so that the vehicle's seat belt rests correctly over the child's shoulder when using the 3-point belt.

Image 3.2: The 8-step height-adjustable headrest.
3.4. 5-Point Harness Adjustment
Ensure the 5-point harness is snug against your child's body without being too tight. Adjust the harness length as your child grows. The harness buckle should be positioned at hip level.
4. Operating Instructions
Always ensure your child is properly secured in the car seat before driving. For children 76-100 cm, use the integrated 5-point harness. For children 100-150 cm, remove the 5-point harness and use the vehicle's 3-point seat belt to secure both the child and the car seat.
Securing Your Child:
- Place your child in the car seat.
- For children 76-100 cm: Fasten the 5-point harness. Pull the shoulder straps upwards to remove slack, then pull the central adjustment strap to tighten the harness until it is snug. Ensure you can fit no more than two fingers between the harness and your child's collarbone.
- For children 100-150 cm: Guide the vehicle's 3-point seat belt through the designated guides. Ensure the lap belt is low across the hips and the shoulder belt is across the center of the shoulder.
- Check that the car seat is stable and does not move excessively.

Image 4.1: Child mannequin correctly positioned and secured in the car seat.
5. Maintenance and Cleaning
The car seat cover is made from durable polyester and is removable and machine washable. To clean, unzip and remove the cover. Wash according to the care label instructions, typically at a low temperature (e.g., 30°C). Allow to air dry completely before reattaching.
Periodically wipe down the plastic parts of the car seat with a damp cloth and mild soap. Do not use harsh chemicals, abrasive cleaners, or solvents, as these can damage the materials.
Inspect the car seat regularly for any signs of wear, damage, or loose parts. If any damage is found, discontinue use and contact customer support.

Image 5.1: Detail of the removable and washable car seat cover.
6. Troubleshooting
If you encounter any issues with installation, adjustment, or function, please refer to the relevant sections of this manual again. Ensure all steps are followed precisely.
Common Issues and Solutions:
- Car seat feels loose after installation: Recheck ISOFIX connectors (ensure green indicators are visible) or vehicle seat belt routing and tension. Push the seat firmly into the vehicle's backrest.
- Harness is difficult to adjust: Ensure the harness is not twisted. Press the harness release button (if applicable) before pulling the adjustment strap.
- Child appears uncomfortable: Adjust the headrest height and harness tension to ensure a proper fit. Check for any clothing interference.
If problems persist, contact tectake customer support for assistance. Do not attempt to modify or repair the car seat yourself, as this could compromise its safety features and void the warranty.
7. Technical Specifications
| Feature | Detail |
|---|---|
| Model Number | 405363-5 |
| Approval Standard | ECE R129/03 (i-Size) |
| Total Dimensions (WxDxH) | Approx. 47 x 47 x 60.5 - 80.5 cm |
| Seat Dimensions (WxD, without reducer) | Approx. 28 x 39 cm |
| Backrest Height | Approx. 49 cm |
| Minimum Age Recommendation | 15 months |
| Suitable Body Height Range | 76 - 150 cm |
| Installation (76-100 cm) | Forward-facing with 5-point harness and ISOFIX |
| Installation (100-150 cm) | Forward-facing with vehicle's 3-point seat belt |
| Maximum Load Capacity | 36 kg |
| Product Weight | Approx. 5.3 kg |
| Materials | Polyethylene (HDPE), steel, 100% polyester |

Image 7.1: Detailed product dimensions.
8. Warranty and Support
For warranty information, product registration, or technical support, please contact tectake customer service. Keep your purchase receipt as proof of purchase. Contact details can typically be found on the tectake official website or on your purchase documentation.
Please have your model number (405363-5) and purchase date ready when contacting support to ensure efficient service.





