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Diono Radian 3R, 3-in-1 Convertible Car Seat, Rear Facing & Forward Facing, 10 Years 1 Car Seat, Slim Fit 3 Across, Jet Black

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Availability: In Stock.
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Arrives Sunday, Mar 29
Order within 18 hours and 49 minutes
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Style: Radian 3R Fits 3 Across


Color: Black Jet


Features

  • 10 Years One Car Seat - from Birth to Booster (5 - 120 lb) it's all you will need. Grows with your child, ultimate protection on every road trip. 4 modes in 1 seat!
  • Rear Facing for Longer - lovingly engineered to keep your child rear-facing up to 50 lb.
  • Fits 3-Across - our famous slim-fit design with zero compromises to safety, space, or comfort.
  • Mechanically engineered from reinforced automotive grade high-strength steel, our unique core shell shields and protects your child.
  • High-quality ComfortPlus Memory Foam, always included.
  • The original and only all-in-one convertible car seat that folds for travel or compact storage. FAA approved for airline use.

Description

The Diono Radian 3R is the original slim-fit 3 across All-in-One convertible car seat, designed to protect from baby to booster seat (5 - 120 lb). Lovingly engineered with the famous Diono steel reinforced frame and now rear facing for even longer, expect 10 years of safety from just one car seat. Designed and engineered with complete rear facing protection, so you can keep them in a safe rear facing convertible car seat for longer up to 50 lb. Built with a mechanically engineered, reinforced steel frame, made from automotive grade high strength steel, the radian is always ready to shield and protect. And when your family grows, the slim-fit design will fit 3 across in most vehicles without compromising child safety or passenger comfort. Our SuperLATCH system (UAS Compatible) makes installation easy and super secure. As travel car seat experts, Diono have naturally built in super portable and convenient features to the Radian 3R with original fold for easy transport and storage and easy remove machine washable covers. The radian is also aircraft certified (FAA approved), so you can take safety with you wherever you go.

Maximum Weight Recommendation: 120 Pounds


Minimum Height Recommendation: 18.1 Inches


Minimum Weight Recommendation: 5 Pounds


Maximum Height Recommended: 57 Inches


Rear Facing Maximum Weight: 50 Pounds


Forward Facing Maximum Weight: 120 Pounds


Rear Facing Minimum Weight: 5 Pounds


Forward Facing Minimum Weight: 22 Pounds


Forward Facing Car Seat Minimum Height: 29.9 Inches


Rear Facing Car Seat Maximum Height: 44.1 Inches


Installation Type: Latch


Orientation: Convertible Seat


Harness Type: 5-Point


Number of Height Positions: 1


Brand: Diono


Age Range Description: Newborn


Infant Toddler Car Seat Type: Convertible Car Seat


UPC: 677726506200


Global Trade Identification Number: 00


Manufacturer: Diono


Item Type Name: All-in-One


Included Components: radian® 3R car seat, detachable rear-facing base, foam harness pads, lap belt cushion, Safe Stop®energy absorbing harness, rear-facing top tether, Instruction manual


Unit Count: 1.0 Count


Manufacturer Warranty Description: 12 months


Item Dimensions D x W x H: 16.1"D x 16.9"W x 28.4"H


Item Weight: 23.02 Pounds


Material Type: Alloy Steel, Plastic, Polypropylene, Polystyrene


Color: Black Jet


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Mar 29

Yes, absolutely! You may return this product for a full refund within 90 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Fits 2 in a row with additional infant seat in Toyota Camry!
Style: Radian 3R Fits 3 Across Color: Black Jet
We bought 2 of these to fit in the backseat of our 2010 Toyota Camry. 1 rear facing, middle forward facing, next to infant (Uppababy Mesa) seat. Middle forward facing was the only way it would fit. Pro’s: slim, sturdy, easy for our kids to get into themselves, latch system is easy/works well. Good customer service from Diono. Our first one didn’t have the rear-facing piece in the box. Cons: * Very heavy! * Tall backside. Check your car seat manual whether a car seat is allowed to touch/rest against the front seat (if rear facing). Now having moved one to the middle back seat (forward facing) on our Honda Odyssey, it sits higher and blocks the rearview a bit. Wasn’t an issue in the Camry. No cupholders- fine, since that wouldn’t fit anyway. Not as much padding, so perhaps less comfortable, but both our kids are fine in them. Overal conclusion: great car seat if you have a tight back seat! ... show more
Reviewed in the United States on February 12, 2025 by Esther

  • Great for Tight Spaces and Growing Kids
Style: Radian 3R Fits 3 Across Color: Gray Slate
This is an excellent car seat for a growing toddler or child. We loved it so much that we purchased one for every car, including the grandparents’. My son had difficulty getting in and out of his previous car seat and struggled with buckling, but he has completely mastered it with this one. He feels more independent and proud that he can get in and out on his own. Another big plus is how space-conscious this seat is. We can comfortably fit two car seats and a third person in the middle seat of our SUV, which is perfect when traveling with extra passengers. Installation is easy, making it simple to move between different vehicles if needed. ... show more
Reviewed in the United States on January 22, 2026 by Purposeful Picks

  • I like it but it's heavy and tricky to install
I got this for my youngest who sits in the middle with booster seats on each side for her brothers. It is narrower than the one it replaces and I really like the red color and design. It looks like a high quality car seat and feels premium. It looks great and fits great in my Range Rover Velar. Overall, I like it but there are a few things to consider: PROS 1. Great looking design 2. Premium feel 3. Easy for my 4-year-old daughter to buckler herself 4. Narrow 5. Comfortable for my daughter CONS 1. It's VERY heavy. If you have to take this seat out from time to time, that might be a concern. This is for my car but my wife would never go for a seat this heavy. It seems like it weighs twice as much as the older Maxi Cosi seat it replaces. If the weight of the seat is a concern, avoid this one. 2. There is nothing intuitive about installing this thing. I had to watch a YouTube video just to find the installation instructions. I'm not kidding - they are hidden in the back fabric and housing. Once you have the instructions, they are not much help. This illustrations are professionally drawn but hard to understand. Even getting the various straps out of the back plastic housings is tricky. ... show more
Reviewed in the United States on February 19, 2021 by Jim S

  • Great Option for Travel
Style: Radian 3R Fits 3 Across Color: Black Jet
We had to replace our previous booster seat. One of the main things I was looking for was FAA approval for flights since we travel and wanted something we could take on the plane for our next vacation. It feels sturdy, safe, and well made. Definitely a great option if you’re looking for a car seat that works both in the car and for air travel. ... show more
Reviewed in the United States on March 9, 2026 by Mirna Velasquez

  • Great car seat, super heavy for travel.
We needed to upgrade our travel car seat and loved that this one folded up nice and compact. Love that it is FAA approved (that was a must for us) It worked really well in the rental car. Our buddy was quite comfortable. Set up was very easy. It is easy to get him in. The release for the belt is kind of tricky to find but easy to use once you got it. We got this one for the same price as the lower model on prime day and are so glad we did the safety plus just for that added comfort. The only drawback for travel is that it is HEAVY!!! ... show more
Reviewed in the United States on September 7, 2025 by Patrick & Amanda O'Connell

  • Easy to move from one vehicle to the other i
Style: Radian 3R Fits 3 Across Color: Gray Slate
Bought this to use in the car and side by side for granddaughter!! The ease of moving it from one to the other is great! The multiple locks and latches are nice! Fits well and slim in the car. Looks great and super sturdy.
Reviewed in the United States on December 14, 2025 by Michelle Garland

  • Fits 3 wide, Great quality worth the $
With the birth of our daughter I needed to go 3 wide on the car seats, which I was told was impossible for my Dodge Charger. Well I purchased 2 of these Diono Radian 3R seats and it worked. The seats are really high quality, loved the added harness protection for toddlers who meet the weight requirement. High quality product and my 2 toddlers are comfortable in them. ... show more
Reviewed in the United States on December 29, 2025 by Joseph Sickler Joseph Sickler

  • Great quality, easy to install and use, and great customer service!
LOVE this car seat. I bought the first one, installed, used, loved it. Was thinking about getting a second one for another car of ours so we wouldn't have to move back and forth between. I left a nice review and mentioned I was thinking about a second one, and the company actually replied back thanking me, and offering me a 20% discount! Of course I took them up on it. This car seat works very well with our grandson that has brittle bone disease and needs to be handled very carefully. Getting him in and out is much easier than our old one, and he's happy in it too. Now between our house and his own house, he has 4 of these seats. Thank you again!! ... show more
Reviewed in the United States on December 14, 2025 by Amazon Customer

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