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Britax Kidfix III M Cosmos Black

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Britax Kidfix III M Cosmos Black Britax Kidfix III M Cosmos Black Britax Kidfix III M Cosmos Black Britax Kidfix III M Cosmos Black

Britax Kidfix III M Cosmos Black

RRP: £170.00
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Available for immediate dispatch
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item features:
  • group 2/3, suitable from 4-12 years (15-36kg)
  • patent pending SecureGuard technology
  • Superior Side Impact Protection (SICT)
  • ergonomically optimised seat
  • ISOFIX or 3-point seat belt installation
Full product information

Britax Kidfix III M

Extending the widely popular Kidfix range, the new Britax Kidfix III M highback booster in Cosmos Black features a longer seating area designed to accommodate children of all sizes, from small to tall, and is recommended for children aged between approximately 3.5 to 12 years of age (15 - 36 kg). Boasting all the usual safety features you would expect from Britax, including SICT and SecureGuard, the Kidfix III M is a great follow-on car seat to see your little one all the way through to 12 years of age. 


Main Features


Ergonomic Seating

Providing unbeatable comfort even for tall children, Britax have extended the seating area of the Kidfix III M by roughly 20%, with an improved shape and extra-soft padding that provides optimum comfort and positioning even on long journeys. 



As the Kidfix III M uses the vehicle's 3-point seat belt instead of a harness, Britax have included SecureGuard, which sits in the centre of the seat around the abdomen and provides a 4th contact point between your child and the seat belt. Keeping that extra contact point across the pelvic bones helps to reduce abdominal force by up to 35%* in the event of a frontal collision, whilst still allowing for some movement during travel. 

*Data collected during Britax Romer internal tests with Q6 dummy, representing an average 6 year old child. 


SICT Side Impact Protection

SICT (Side Impact Cushion Technology) acts as a barrier between the car seat and the car's exterior, reducing impact force and absorbing energy before it reaches your child in the event of a side-on collision. Simply pop the SICT out from the seat on the side closest to the door to provide your little one with additional protection should you find yourself in an accident. 


Adjustable Headrest

The ergonomic headrest on the Kidfix III M is designed to help support your child's head if they fall asleep on long journeys, and can be adjusted to multiple height positions with just one hand, even when your child is in their seat. This helps to accommodate their changing needs as they grow and ensures the headrest is always in the best possible position; just above their shoulders. 


V-Shaped Backrest

The V-shaped backrest on the Kidfix III M is designed to provide optimum support for your child as they grow, ensuring plenty of space for their back and shoulders. The backrest also adjusts to suit the angle of your vehicle's seat, allowing for a better fit and more comfortable positioning for your child. 


Highback Booster Protection

The protection offered by the Kidfix III M highback booster is threefold: the shell itself provides complete protection from head to hip, which is especially useful in side-impact collisions; the upper and lower belt guides help to hold the seat belt in the safest position; and the extra padded headrest protects your child's head and neck whilst adding an additional level of comfort for long rides or on-the-road naps. 


Easy Clean Up

The removable, machine washable seat cover is great for messy kids, spills, and accidents. Simply pop the cover off and stick it in the washing machine to make cleaning up super quick and easy. 


The Britax Kidfix III M is the perfect choice for families looking to replace their infant car seat with a super protective, ultra comfortable highback booster that will last right the way through from toddlerhood to pre-teen. 

  • group 2/3, suitable from 4-12 years (15-36kg)
  • patent pending SecureGuard technology
  • Superior Side Impact Protection (SICT)
  • ergonomically optimised seat
  • ISOFIX or 3-point seat belt installation
  • adjustable V-Shaped backrest grows with your child
  • height adjustable ergonomically designed headrest
  • intuitively positioned seat belt guides over shoulders & pelvis
  • removable, padded cover

Suitability: Suitable from 4-12 years (15-36kg)


Group: 2/3


Installation: Forward Facing, ISOFIX/3-point seat belt




Height: 67-85cm


Width: 54cm


Depth: 43cm


Weight: 7.5kg 

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We aim to dispatch all “available for immediate dispatch” orders placed by 12pm the same working day.  Exceptions include made to order items for example some nursery furniture or direct ship items sent by the manufacturer directly to the customer.  In these cases an approximate delivery schedule is shown next to the product.


Our standard delivery cost is £4.99 for orders under £49.99.  Orders over £49.99 is free of charge.  Exceptions apply please view our Delivery & Dispatch page for detals.
Any items “available for immediate dispatch” will have the choice of standard delivery (2-3 working days) or express delivery (1-2 working days) this can be selected during the checkout process.
Orders for delivery to select Scottish post codes and Scottish Highlands, UK Islands & Northern Ireland may incur additional costs. These schedules would exclude made to order and direct ship items. 
Please note that some nursery furniture deliveries will be to the customer's door, this may exclude internal apartment doors.
For more information please click here


We offer a 14 day return policy allowing you to decide if the goods are as expected.  During this time you may return the goods at your expense or request collection with our courier company at a cost of £18 per parcel.  If the item has been used you will be unable to return the item under distance selling regulations.
Any damage in transit of shortages must be reported with 48 hours of receipt of the goods after this time claims will not be accepted.

Tutti Bambini Returns:

You can request to return a Tutti Bambini item within 28 days of delivery providing the item is in its original packaging and in pristine condition. The Following charges will apply dependent on the original delivery method:

  • Single items weighing less than 15kg- £15.00
  • Single items weighing more than 15kg- £25.00
  • Non-assembled room sets- £50.00
  • Assembled room sets- £150.00

For non-assembled and assembled room sets, the above charges will also apply if the customer is not present to receive delivery.

For more detailed information please read our terms and conditions.

Nursery Furniture

Wood samples are available upon request.

Delivery of nursery furniture to certain locations within the United Kingdom may be restricted.  For example Isle of Wight, Isle of Man, certain Scottish postcodes, Highlands & Islands, and Northern Ireland. 

For our furniture terms and conditions of sale please refer to our terms and conditions page under the section Nursery Furniture Return Conditions

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Britax Kidfix III M Cosmos Black