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Britax RömerDualFix M i-Size

i-Size baby to toddler
Isofix installation only
Extended rear-facing seat

£319View retailers

Test score

Lowest available price

£319Kiddies Kingdom

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The Britax Römer Dualfix M i-Size is a baby and toddler car seat that can be used rear-facing until your child reaches four years old. It also features a handy 360-degree swivel design, which should make it easier to get your child in and out. Did our crash testing uncover any issues with this baby and toddler car seat? Read our full test review.

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What is it?
How safe is it?
Is it easy to fit?
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KEY TEST RESULTS
Safety rating
Fitting in car
Comfort of your child

Jan 2025Last checked by Which?
Sept 2018First reviewed by Which?
Jun 2018Released

The overall Which? test score is made up of the following star ratings, all determined by our rigorous lab tests.

How we test baby and child car seats

22 May 2025

Safety rating

Overall
Rear-facing i-Size (Isofix)
Forward-facing i-Size (Isofix)

How we test safety rating

The overall safety score is made up of the results of crash testing (front crash; side crash) seat design, stability in the car and belt routing. Our crash tests go beyond the legal minimum requirements for UK car seat regulations and are conducted at higher speeds and forces than the regulations require. We feel our tests more accurately reflect what could happen in a real life crash.

Fitting in car

Overall
Buckling up
Avoiding misuse and instructions
Cleaning
Space required in car

How we test fitting in car

Fitting and using includes: How easy it is to install the seat correctly in the car. How easy it is to strap a child securely into the seat. How well the seat is designed in order to prevent incorrect use. How easy the seat cover is to remove and wash. How little space the seat takes up in the car and how comfortable your child is in the seat.

Ergonomics

Overall
Comfort of your child

How we test ergonomics

Our experts conduct an ergonomic assessment of each seat to make sure your child will be in the best position when travelling, along with the level of padding and support. Our tests also reveal how much space this car seat takes up in the back seat of a car and how easy it is to get your child in and out of the seat. Plus, our eagle-eyed car seat experts will check whether this seat affects how much space any front passengers have. This assessment was introduced to our site in May 2015. If a seat does not have this score, it was tested before May 2015.

General
Height of child	61-105
Seat size	i-Size baby to toddler
Age group	Baby to toddler
Direction of travel	Rearward-facing/forward-facing
Extended rear-facing seat	Yes
Installation type	Isofix installation only
Harness or shield seat	Harness
How is the child held in the seat?	5 point harness
Manufacturer URL	www.britax.co.uk

Features
Adult seat belt	No
Isofix integrated into seat	Yes
Isofix base	No
Belted base	No
Type of Isofix	Isofix connectors and support leg
Swivel seat	Yes
Weight of seat (kg)	16.3kg
Part of a travel system?	No
Harness height adjustment	Moves with headrest
Recline	Yes
Adjustable headrest	Yes

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Kiddies Kingdom
In Stock£319

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Britax RömerDualFix M i-Size

Lowest available price