Britax Römer Kidfix III S Cosmos Black

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Britax RomerSKU: 2000032374

£152 £190
Use ‘BABY5’ in cart for a 5% discount at checkout!
Available for immediate dispatch

The new Britax Römer Kidfix III S in Cosmos Black is a forward-facing highback booster that's packed with useful safety features and ergonomic designs that make it one of the most comfortable seats on the market. Suitable from 3.5 to 12 years of age (15 to 36 kgs), the Kidfix III S protects your little ones from head to hip and supports kids of all sizes as they grow throughout the years. The highly durable, easy-care materials ensure the seat remains in good condition for the entirety of its use, and make cleaning up day-to-day messes quick and simple. 


The newest feature on the latest addition to the Kidfix family is the shock-absorbing foam XP Pad, which sits across your child's chest and around the vehicle's seat belt. The XP Pad helps to absorb up to 30% of energy in the event of a frontal collision while preventing your child's chin from rebounding off of their chest. The additional padding also helps to limit the jerking forward head movements that often occur in this type of accident, protecting your little one's delicate neck from further injury. Finally, the XP Pad cushions your vehicle's seat belt, limiting discomfort on the road and potential injury in the event of a collision. 

The SecureGuard technology featured on the Kidfix III S is instrumental in protecting your child's abdominal area should you ever find yourself involved in a collision. SecureGuard works by adding an additional 4th point of contact instead of the standard 3 created by your vehicle's 3-point seat belt, resulting in higher dispersion of force across a wider surface area. SecureGuard also holds the seat belt in the optimum position to reduce the risk of injury, and has proven to reduce abdominal forces in the event of a frontal collision by as much as 35%! 

The advanced Side Impact Cushioning Technology (SICT) is the best way to protect your child in the event of a side-on collision and works by providing an additional barrier between your child's seat and the door, reducing the amount of space between the two and helping to absorb energy and force before it reaches your little one. The SICT system is easy to use, simply pop it out from the top of your child's seat on the side closest to the door. 

The adjustable headrest of the Britax Romer Kidfix III S is designed to suit children of all ages, even as they grow, and should be positioned just above your child's shoulders for optimum protection. It can be easily adjusted with just one hand, and keeps your child's head supported if they fall asleep, ensuring they are kept safe should they be sleeping when you encounter an accident. 


The seating area of the Kidfix III S is approximately 20% larger than similar models on the market, providing plenty of space for growth. The improved shape and additional padding makes for a comfortable seat even for older children, and the ergonomic design ensures a comfortable seating position for children of all sizes. 

The backrest of the Kidfix III S is V-shaped, leaving plenty of room for your child's back and shoulders as they grow and develop. Additionally, the backrest of the seat automatically adjusts to the angle of your vehicle's seats, providing a more comfortable and natural position for your little one when on the road. Finally, the headrest is well padded so your child can nap or relax comfortably in their seat without straining their neck. 

Additional Information

Spills and messes are inevitable when you're travelling with children. That's why the covers of your Britax Kidfix III S can be easily removed and are suitable for machine washing, so you can keep your seat looking fresh and new throughout its life.

The Kidfix III S can be installed into your vehicle in two ways: either with the ISOFIX connectors and your car's 3-point seat belt, or with the seat belt alone. If you are unsure whether your vehicle has ISOFIX anchorage points you can speak to your car dealership, check with Britax's Fit Finder, call us on 0117 986 8184, or send us an email. Our experienced team would be more than happy to discuss whether this seat is the right fit for your vehicle. 

The Kidfix Collection features a wide variety of amazing car seats by Britax Römer, click here to view the full range of Kidfix car seats from Britax Römer. 

Key Features

  • Protective from head to hip
  • Removable machine-washable cover
  • Shock-absorbing foam pad
  • Large ergonomic seating area
  • Durable easy-care materials
  • SecureGuard helps protect your child's abdominal area
  • Advanced Side Impact Cushioning Technology (SICT)
  • Adjustable headrest and backrest
  • ISOFIX or belted installation


Age suitability: from 3.5 to 12 years
Weight suitability: from 15kg to 36 kg

Dimensions: 85cm x 54cm x 43cm

Weight: 8kg

If you place an order by 12pm between Monday to Friday of an item marked as available for immediate dispatch we will ensure the order is dispatched the same day.  Orders received after that time will be dispatched the following working day.  
Availability denotes the length of time the item will take to be available to dispatch. 
Shipping denotes the duration of time that an items takes to reach its destination the either our warehouse or manufacturer's warehouse.  For example an item with "Available in 7-10 working days" and "Standard Delivery" should be expected in 9-12 working days.  Please note working days excludes weekends and bank holidays. 

Our secure website and payment gateways perform a number of security checks against an order.  Any errors on the order could result in delays while we attempt to contact you to clarify any inaccuracies.  At Baby & Co we use a number of carrier services to ensure prompt and speedy delivery, this may include using more than one carrier for an order, however this is rare.
Your order may be dispatched from more than one location including our warehouse or directly from the manufacturer this may result in your order arriving on more than one consignment.  Aside from made to order items and direct delivery we offer the following delivery options. 

With the exception of made to order items and products sent directly by the supplier below you will find our standard delivery terms.  Please note that we only ship within the United Kingdom. 

Please note the following brands only deliver to UK mainland post codes, excluding some Scottish post codes:- Ickle Bubba, Boori, East Coast, Tutti Bambini, Mamas & Papas, Silver Cross furniture.

Please note that some nursery furniture deliveries will be to the customer's door, this may exclude internal apartment doors.

Standard Delivery
Region Rate Delivery Schedule
U.K. mainland Orders over £49.99 - Free
Orders £49.99 or under - £4.95
2-3 working days
Scottish Highlands £18 per order
U.K. Islands
& Isle Of Wight
£18 per order
Northern Ireland £9.99 per order*
Please note - our carriers only work Monday to Fridays (8am - 6pm). We regret our carriers cannot deliver at a specific time. ALL deliveries must be signed for.


Express Delivery
Region Rate Delivery Schedule
U.K. mainland Orders over £49.99 - £7.95
Orders £49.99 or under - £9.99
1-2 working days
Scottish Highlands £18 per order
U.K. Islands &
Isle Of Wight
£18 per order
Northern Ireland Not available *
Please note - our carriers only work Monday to Fridays (8am - 6pm). We regret our carriers cannot deliver at a specific time. ALL deliveries must be signed for.


*Please note there may be some delays shipping goods to Northern Ireland.

All returns are processed through the retailer and not the manufacturer; please contact us regarding any after sales issues. We endeavor to offer an impartial returns procedure for the benefit of all parties. To enable us to process your claim as efficiently as possible please follow this procedure, failure to follow this procedure could result in delays in processing your claim or return. 

In the first instance contact our returns department on or write to us with the following information:

  • Order Number
  • Name (Person who placed the order)
  • Contact telephone number.
  • Date of Purchase
  • Faulty Item (Product description)
  • Details of Fault (Description of fault)
  • If possible digital photos could also be sent to help identify the problem.

We will then, depending on the issue, either contact you to discuss the matter further or issue you with a returns authorisation number. Please note returns sent back without a returns number may be refused or could result in delays in processing.

If it is felt that the goods need to be returned for inspection you will need to do the following.

  • Box the item ready for collection. It is wise to retain the original packaging for this purpose. Our shipping company will not collect items which are not properly packaged
  • Contact us at to arrange collection. Please book your collection at least 2 days in advance and between Monday – Friday. Collections are usually made during the afternoon via Parcel Force. Please allow at least a 4 hour window when you will be available. If a collection is scheduled and you are not home as arranged you will be charged a £8.00 for the aborted collection
  • Please include your Returns Authorisation Number (RAN), proof of purchase and a description of the fault.

If you are not satisfied with your purchase, please return unused and its original packaging with any tags still attached for an exchange or refund. We do not accept returns on personalised items or hygiene sensitive items including duvets and mattresses once they have been removed from their protective wrappers. This does not affect your statutory rights.

  • We will refund the full amount to the original payment method excluding any shipping costs
  • Credit/debit card refunds can take up to 10 working days to be processed by your bank, we are unable to expedite this process.
  • Returned orders remain the customer's responsibility until safely received by us. We recommend using a reliable carrier and insuring the parcel for loss or damage. Alternately you can take advantage of our carrier service please contact us for a quotation.
  • Replacements, refunds or exchanges of damaged or incorrectly ordered items will not be processed until the original items are received and inspected.
  • If goods form part of a bundle then the whole order will need to be returned or the remaining items will revert to their normal recommended retail price and you will be refunded accordingly.
  • We reserve the right to refuse a refund if the condition of the goods are subject to normal wear and tear, misuse or damage.

Please note we are unable to offer a loan or replacement product while your return is being inspected or repaired. Proof of purchase must accompany any warranty claim. Most nursery items come with a 6 months guarantee; however some products have longer warranty periods, please check your warranty book for more details. This does not affect your statutory rights. If a fault develops within the guarantee period, we will arrange collection and inspection in our workshop. If the failure is confirmed to be due to a manufacturing fault we will arrange repair, or replacement if the repair in uneconomical.
If the fault is due to fair wear and tear, damage or misuse we will quote for a rectification and you will also be liable for the carriage charges, which are currently £18 per parcel*.
In the event of a dispute as to the cause of the failure the product will be sent to the manufacturer who will establish if the fault is covered by the manufacturer’s warranty. 
In the event the manufacturer identifies the fault is due to fair wear and tear, damage or misuse you will be liable for all carriage costs and any repair costs if you wish the product to be repaired.
Our workshop will be happy to quote for any non-warranty repair. All returned product must be carefully packed in cardboard. It is wise to retain original cartons for this purpose. If a collection is scheduled and you are not home as arranged you will be charged £8.00 for the aborted collection.
For furniture returns please read our terms and conditions page under the section Nursery Furniture Return Conditions.

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