Britax Römer Advansafix M i-Size Cosmos Black

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Available for immediate dispatch

The Advansafix M i-Size by Britax-Romer is designed to protect children from 15 months all the way to the age of 12 years. Offering safety you can rely on, and maximum flexibility for ultimate convenience and comfort, the Advansafix M i-Size is the perfect car seat to take protect your little one for years to come.

Approved to the new i-Size regulation, the Advansafix M can be converted from a harness seat to a highback booster seat in a few simple steps while also allowing your child to benefit from 5-point harness protection up until they reach 21kg.

Thanks to the Flip&Grow function, this amazing car seat can easily change from utilising the integrated 5-point harness, to the car’s 3-point seat belt when your child is ready to move to the next stage of car safety. What’s more, because you don’t have to remove any parts when changing stages, you can simply switch it back easily at any time. The EasyRecline function also means that you can adjust the recline settings without readjusting the entire installation, so keeping your kid comfortable on each and every journey is easier than ever.

With Britax-Romer you can be assured of attention to quality and safety in every car seat. They design, create and produce their products all under one roof to ensure every aspect of development is overseen with the utmost attention to detail and they even oversee regular in-house, state-of-the-art crash testing at their facility as well. The Britax-Romer uses their own patented Pivot Link ISOFIX system which is designed to direct the force downward first, then forward more gently second - a system which greatly reduces the risk of head and neck injury for your child in case of collision.

The safety doesn’t end there though. The Advansafix M i-Size car seat uses a 5-point harness which has been proven to be the safest way to secure your child by distributing the impact forces evenly to help protect your little one from all directions. This amazing car seat also features soft neoprene performance chest pads that fit comfortably on your child’s chest, to both add more comfort to the 5-point harness but also further reduce your child’s movement in the event of collision.

The SecureGuard also helps protect your infants abdominal area by adding an extra contact point when using your car’s 3-point seat belt with the car seat, so you can be ensured of maximum protection while giving your child the freedom of movement during each journey. 

Once your child has graduated to the highback booster, the Advansafix M i-Size offers protection for your child in 3 ways: by providing head to hip protection with the seat shell, by ensuring correct seat belt positioning using the upper and lower belt guides, and by the padded V-shaped headrest that cradles your child’s head for ultimate protection.

The V-shaped headrest is specially designed to ensure optimal protection in the event of a side collision by controlling the movement of your child’s head. It is also easily adjustable from the front of the seat so no matter how fast your child is growing you can always adapt to keep them comfortable quickly and easily. The Top Tether also offers an even higher level of stability and security for your child than with conventional tethers by minimising the rotation of the car seat in the event of collision.

If your little one makes a mess in the back seat with a classic car picnic, then cleaning the Advansafix M i-Size is as easy as removing the cover and putting it in the washing machine. The neoprene performance chest pads can also be easily removed without disturbing the harness so you can clean up quick and get on your way again.


Dimensions: 60 – 83 x 44 x 47 cm
Weight: 11 kg

Age suitability: 15 months - 12 years 
Height suitability: 76 - 150 cm
Direction of travel: Forward-facing

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.  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:- Kidsmill, Europe Baby, 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 £18 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 £18 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.


All returns are processed through the retailer and not the manufacturer; please contact us regarding any after sales issues. We endeavour 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.

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 come with a 12 months guarantee. Check your instruction guide or warranty book for more information. 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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