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Radian All-in-One Car Seat Installation and Fit Guide

Radian All-in-One Car Seat Installation and Fit Guide

Car Seats
First timer or looking to refresh your knowledge? Here’s how to spot common mistakes and ensure you have achieved the perfect fit with your Radian®

We all forget things sometimes. Parenting is a lot to remember. Like, a lot. And it changes along the way. Take car seat safety, for example. Rear-facing installation and fitting is different than booster mode. Booster mode installation and fitting is different than forward-facing with a 5-point harness. Remembering all that information is difficult, but it is super important that your car seat and Very Important Passenger are as safe and secure as can possibly be.

To help, we’ve teamed up with our very own CPST, Scott, to give you a guide on how to install your Radian® all-in-one convertible car seat, and ensure you achieve the perfect fit. Every single time. Plus, we’ve got a whole channel of installation videos for every Radian® model in rear-facing, forward-facing with harness, and booster mode. You can head there by clicking on the images below!

1. The most important rule for car seat installation and fitting is read the manual. Not only your car seat manual, but your vehicle manual too.


    2. Harness Straps

      Rear-facing passengers should have the harness straps positioned at or BELOW their shoulders. Forward-facing passengers should have their harness straps positioned at or* ABOVE their shoulders.

      *Some brands say at OR above. Diono car seats require harness straps to be ABOVE shoulders when forward-facing. Always check your manufacturer's manual.


      3. Chest Clip

        The chest clip should be positioned at arm pit level. A common car seat mistake is thinking that the chest clip should be positioned to keep your child restrained in their seat in a crash. Truth is, it’s more likely to break or come undone, and that’s totally normal! The chest clip is a pre-crash positioning device designed to keep the harness straps positioned correctly over your child’s shoulders.


        4. Harness Straps – The Pinch Test

          Many parents and caregivers fear that the harness will be too tight, causing discomfort for their child. Here’s why it’s important to ensure the straps are fitted correctly.

          • A properly tightened harness is one you cannot pinch when checked at the collar bone. The harness transfers the crash forces to the strongest parts of your child’s body and then to the car seat.
          • It will reduce the movement of your child in a crash and ensure they remain in the safest position within the protective shell of the car seat.
          • The 5-point harness greatly reduces the chance of your child being ejected from the car seat.
          • A properly secured harness keeps the child positioned correctly in their car seat for the entire ride.

          5. Bracing – Does Diono Allow Bracing?

            Bracing is when the back of a rear-facing car seat touches the vehicle seat in front of it. At Diono we DO allow bracing, but ONLY if your car manufacturer allows it. While it's essential to read your car seat manual before any installation, it is also super important to refer to your vehicle manual too, as it will have lots of information about properly installing car seats.

            Radian® 3R

            Rear - Facing

            Forward - Facing 

            Booster

            Radian® 3RXT®

            Rear - Facing

            Forward - Facing

            Booster

            Radian® 3RX

            Rear - Facing

            Forward - Facing

            Booster


            Radian® 3RXT® SafePlus™

            Rear - Facing

            Forward - Facing

            Booster

            Radian® 3QXT FirstClass™ SafePlus™

            Rear - Facing

            Forward - Facing

            Booster

            Radian® 3QX

            Rear - Facing

            Forward - Facing

            Booster

            Radian® 3QXT

            Rear - Facing

            Forward - Facing

            Booster

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