Diono Radian 3RXT
Steel frame, narrow profile. The classic three-across solution if you have a sedan and a third child coming.
- Price
- $370 each
- Age range
- 4–120 lb
- Twin verdict
- buy two
- Buy used?
- buy new
Verdict
Buy two
From the desk
If you need three car seats in a back row, the Radian is one of the few seats that genuinely makes that geometry work. It's about 17 inches wide and folds nearly flat, which means you can install three abreast in a midsize sedan or get a fourth person into the front of the back seat in a pinch.
The Radian is heavier than most convertibles (around 25 lbs) and the install is fussier than the Graco SlimFit. The American version (Radian 3RXT) is somewhat over-engineered: aluminum reinforcement, eleven-position recline, super-heavy buckle. The trade-off is that you'll keep this seat for years. A single Radian goes from rear-facing infant to forward-facing booster, all the way through age 8.
Twin parents we know mostly buy two Radians when they have a third child or know they'll have one soon. If you'll only ever have two, the Graco SlimFit is the simpler choice.
Why we say buy two
Two Radians if you need three-across or expect a third child. Otherwise, two SlimFits cover the same fit problem with less complexity.
Where to buy
- Buy at Amazon (US) →
Amazon (US)
Some buy links earn us a small cut, at no extra cost to you. We still recommend skipping plenty of things, so it balances out.
Pair with
Other convertible car seats picks twin parents put on the same registry.
Britax · Convertible Car Seats$330 eachBritax Marathon ClickTight
ClickTight install removes most of the install errors that plague twin parents installing two seats fast.Buy 2Buy new
Britax · Convertible Car Seats$400 eachBritax One4Life ClickTight
All-in-one (rear-facing infant through booster). One seat per twin from birth to ~10 years.Buy 2Buy new
Chicco · Convertible Car Seats$330 eachChicco NextFit Zip
Mid-priced convertible from a known-reliable brand. Generous rear-facing limits.Buy 2Buy newYou might also need
Categories twin parents commonly pair with convertible car seats.
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