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The original, and the best, 3 across car seat - Meet the Diono Radian®

The original, and the best, 3 across car seat - Meet the Diono Radian®

Car Seats
Busy back seat? Here’s just some of the reasons why the Diono Radian is the best 3 across car seat with narrow slim fit design for growing families!

Busy back seat? We got you. Diono Radian’s have been the best 3 across car seat for growing families for more than a decade. That's why over a million children travel in a Diono car seat every day.

As parents ourselves we quickly discovered the need for a car seat that would fit 3 across comfortably in the back seat of a midsize vehicle. Our engineers began looking at ways to make this happen, using extensive research into common vehicle sizes not just in the USA but across the globe, to determine what dimensions we were able to use.


Once this was understood, they wasted no time getting to the drawing board and began innovating unique concepts and designs that enabled the standards of safety we expected, that would comfortably fit a child, within a slim fit, narrow frame.

At Diono, we’re famous for our steel core at the heart of our all-in-one convertible car seats, and we made no exception to include this when we began engineering our latest model, regardless of the slim fit design. Our engineers built from within, starting with the famous steel core.

Next came side impact protection, using a combination of interlocking EPP and EPS foam* to create layers of protection within the frame. Each of these safety features are included across the entire Radian® collection, without compromising the original 3 across slim fit design.

But it wasn’t just safety that was important, we wanted to ensure child passengers were traveling comfortably in their car seat. We engineered a wide seat base that can comfortably accommodate growing passengers, while still being cleverly narrow enough to fit 3 across. We’ve expertly utilized all space within our car seats to make the most of it where needed and be smart where it isn’t.


At Diono, we’ve been pioneering rear facing travel since we started and nothing about this changed when we began designing 3 across car seats. Whichever way you choose to ride, or combination of ways, Radian® is able to fit 3 across the back seat, that means you can make the most of rear-facing for longer and forward-facing combinations. Plus, with five ways to travel from birth to booster, Radian® may be the only car seat you ever need for up to 10 years of adventure 

*Q Series models only.

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