Car Seat – Isofix, Isofix Base, Top Tether?

car seat

Already in the previous entries of the series How do I choose my first cart? we talk about the feeling that comes over us when we start looking at baby carriages. If we are new parents, there is a Chinese-sounding language that we have to learn.
As part of the stroller or separately, if we have a car and we want to transport our baby with it, we will need a car seat, for newborns a Group 0 or Group 0+, then group 1, 2, and 3. And when we start to look … They will ask us, do you want with Isofix? Do you have Top Tether? Do you buy the three-piece stroller or do you buy one separately? And our face says it all … We have no idea …

What is the Isofix? Is it mandatory to use it?

The two most common ways of attaching the seats to the car seat are with seat belts or with Isofix. The latter is a system for fixing the seat by means of three anchoring points directly to the vehicle (without using the seat belts). It is not mandatory to use it, but it is an advance in safety since we will never forget to “tie” the chair as some mother told us. Before buying a chair with Isofix, check that your car has the anchors.

Top Tether, Universal, Semi-Universal 

These expressions refer to the third anchor point of the chair. Two points are fixed between the backrest and the car seat, but there is a third point, the anti-tip fixation, which prevents the seat from tipping forward in the event of an impact.

In the case of Top Tether, it is a belt that comes out of the upper part of the chair and is fastened behind the seat. This travel system is considered Universal.

If the third point or anti-tip system is a leg resting on the vehicle’s floor, we call it the Semi-Universal system. In the case of Group 0 and 0+, the latter is the most widespread system, for this reason, if we want to install the baby carrier with the Isofix system, it is necessary to buy an Isofix base

Before deciding on a model or a system, you must first check whether or not your car has Isofix system anchors and if it has a hitch for the Top Tether.

If I buy a three-piece stroller, do I have to buy the Isofix base?

Not necessarily. You should check with the carrier manufacturer. As group 0 or 0+, it must be approved to be fixed with seat belts. Each brand usually has its own Isofix base as a compliment.

The three-piece strollers include the carrycot, pushchair, and baby carrier (group 0+).
The baby carrier is adapted to the Isofix system, which means that it can be installed in the car with the Isofix system if the Isofix base is purchased.
But it is also prepared to be installed with the seat belts, so if your car does not have Isofix, or you do not want to buy the base, Group 0 can also be used by fixing it with the belts. Here you can see the video of how it is installed:

What do I do if we have two cars, one has Isofix, and the other doesn’t? Buy two chairs?

In these cases (which are the majority because in the useful life of a car seat we do not always use the same car) the best choice is a car seat that can be installed with the belts and with the Isofix system, such as Group 0 from Group 1-2-3 that is fixed with Top Tether and with the belts if necessary. The Isofix base of our strollers can also be attached with the belt, which makes it even more versatile.

Is it necessary to buy the adapter to be able to connect Group 0 to the chassis of my stroller?

If you buy a 3-piece in the pack, the adapter is included so that you can put the baby carrier on the chassis, which is a very comfortable option. Other models of baby carriers have their specific adapter for some strollers. In our case, we sell an adapter for the most popular baby carriers, such as those of the Roma Vita² brand. For a walk or if the baby is going to spend a lot of time inside, it is best to use the carrycot. But for active walks or for running, it is better to use group 0 because it includes a harness that secures the baby during exercise. If you are using the carrier with the chassis, you will need an adapter.

  • Suitable from newborn – 15kg
  • Lightweight aluminum frame
  • All-round suspension
  • Large hood with viewing window
  • Unique compact fold

Improving safety is a constant in the creation of baby products and new systems make it easier for us to use the products. We must know them and inform us of their correct use. The versatility of car seats seems to us one of the most important elements since we transport them in different vehicles for the little ones.
If you are looking for a chair and have questions, contact us.

Choosing the car seat is not an easy task but we hope that by clarifying some concepts it will be easier for you to decide what you and your baby need.

If you found this entry interesting, share us on your social networks and subscribe to our newsletter. You will receive a GUIDE ON HOW TO CHOOSE YOUR BABY STROLLER To begin we explain the parts of the stroller,  including all their names. Then we show you the 5 questions you have to ask yourself before choosing a stroller. To download the Guide, click on this link and subscribe to our newsletter. You will not receive spam, but in addition to the Guide, useful information for future parents, such as what is the Top Tether, if it is necessary to buy the Isofix base, and similar things.

So that you can tell us about your real experience
Share your opinion. 

See also: A Guide to Maintaining Your Baby’s Oral Health


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