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Diono Radian 3RXT Safe+ Convertible Car Seat

Diono Radian 3RXT Safe+ Convertible Car Seat

Regular price $349.99
Regular price Sale price $349.99
Sale Sold out
Color : Black Jet
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The original 3-across, all-in-one car seat just got better. Upgraded with 18 improvements from the award-winning original Radian 3RXT, the Diono Radian 3RXT Safe+ Convertible Car Seat features Diono Safe+ engineering, Safe+ anti-rebound panel and advanced Safe+ side impact protection for complete protection from birth to booster.

The Radian 3RXT Safe+ adapts as your child grows from birth up to 120 lbs, making it the only seat they'll ever need. Plus, its slim fit design allows 3-across seating in most vehicles so you can accommodate all your little ones in ultra-safe and comfy car seats!


  • Adapts as your child grows from rear-facing to forward-facing mode, birth to booster, up to 120 lbs
  • Slim fit 3-across in most midsize vehicles
  • Easy-adjust 12-position headrest
  • 6 layers of Safe+ side impact protection and Safe+ testing
  • Steel anti-rebound bar reduces rebound rotation by up to 50% for extended rear-facing travel up to 50 lbs
  • Safe+ steel-reinforced frame and core to shield and protect
  • Newborn travel wedge, anti-rebound bar, and infant positioning liner make rear-facing travel extra safe
  • Safe+ engineering is unique combination of engineering features and testing to the highest safety standards
  • Machine washable cover
  • FAA approved; folds for travel
  • Easy LATCH installation
  • Memory foam cushions

Installation Options

  • Rigid LATCH
  • Seatbelt Installation 

What's Included

What's Included

  • Radian 3RXT Safe+ Convertible Car Seat
  • Rear-Facing Base
  • Infant Positioning Liner
  • Newborn Travel High Wedge
  • Cup Holder
  • SafePlus™ Steel Anti-Rebound Bar
  • Harness Pads and Lap Belt Cushion
  • Rear-Facing Top Tether Strap


Weight/Height Capacity 

  • Minimum User Weight: 4 lbs
  • Maximum User Weight: 120 lbs

Rear Facing:

  • Minimum weight: 4 lbs
  • Maximum weight: 50 lbs
  • Maximum weight with LATCH: 35 lbs

Forward Facing:

  • Minimum weight: 22 lbs
  • Maximum weight: 65 lbs
  • Maximum weight with LATCH: 40 lbs


  • Minimum Weight: 40 lbs
  • Maximum Weight: 120 lbs
  • Maximum Height: 57.1"

Weight and Dimensions 

  • Weight: 28.1 lbs
  • Dimensions: 28.5"H x 17"W x 16"D

Materials and Care Instructions

  • Covers: Machine wash cold, line dry. Shell and Components: Spot clean

Compatibility + Accessories


  • Radian Car Seat Travel Backpack
  • Ultra Mat and Heat Sun Shield Car Seat Protector
  • Radian Rear-Facing Angle Adjuster
  • Radian XL Cup Holder - 2 Pack

CPS Techs

What is a CPS tech?

A CPS tech is a Certified Passenger Safety Technician. Our Cubby Moms who have certified as CPS techs are specially trained on how to properly install car seats and booster seats, ensuring they know everything there is to know about keeping children safe in vehicles.
Through required continuing education courses and hours of personal research and team training, our CPS techs are able to remain up to date on the latest technical information regarding child safety.
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How does a CPS tech get certified?

In order to become certified, each prospective tech must attend The National Child Passenger Safety Certification Training Program. After intensive classroom instruction, they must pass a variety of written tests, demonstrate their knowledge through hands-on skills assessments, and perform safety checks at a check-up event before becoming certified. They learn the ins and outs of car seat installation possibilities, installing car seats in different vehicles, harnessing methods, and more. The car seat and safety industry is constantly changing, so our CPS techs here at The Baby Cubby are an invaluable resource for parents purchasing a new car seat, or for ones who simply want someone to double check that their current car seat is properly installed.
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How can I get in contact with a CPS tech?

You can visit our store during regular business hours to consult with a CPS tech. This is a service we provide all year round because we’re passionate about helping parents and keeping kids safe! If you’re not local, you are always welcome to contact The Baby Cubby via phone to get the peace of mind our highly-trained techs can offer when it comes to child car safety. To contact our CPS techs, use the options listed below.





Car Seat Return and Shipping Policy

Car Seat Returns

Due to safety concerns, only unopened car seats can be returned. Safety is our top priority and we want you to keep your kiddos safe. If you have any questions, please reach out to 

Car Seat Shipping

Free Shipping applies to standard shipping orders over $95 within the continental U.S.A. Unfortunately, orders shipping to Alaska, Hawaii, Puerto Rico, or APO/FPO addresses do not qualify for free shipping.
Large furniture items that must ship as freight such as cribs, gliders and dressers have a separate furniture delivery fee.

Free 5-7 days shipping is available on every order over $95 (excluding taxes and shipping fees) in the continental U.S.A. If you are in need of expedited shipping, the cost will be dependent upon your area and how fast you are wanting it shipped to you. You can get a shipping quote in your cart at checkout.

Shipping Timeline

For standard shipping, FedEx and USPS have up to 5-7 business days to deliver your order. However, most items arrive within 3-5 business days.

To track your package, follow one of the links below:

United States Postal Service (USPS) Tracking:

FedEx Tracking:









Best Price Guarantee


We understand that caring for a baby isn’t cheap
and that baby gear and supplies quickly add up. If
you find a lower price on any item that we sell, we
will gladly match it.

The product must be the exact same color/style/size
and be in stock on competitor’s website. Unfortunately,
we cannot price match auction-based websites. Some
brands and manufacturers are excluded from our price
match policy. Some items have a 1 per person price
match as well.


To obtain a price adjustment, please contact email
Customer Service at


A one-time price adjustment per item will be honored
when items are purchased at full retail price and the
merchandise (of the same style, color, and size) is
discounted within 14 days of the original purchase date.
Price Match Exceptions:
Items purchased with a promo code or discount code are
not eligible for price adjustments.
Price adjustments are not provided during Black Friday or
Cyber Monday sales.
The following brands are not eligible for price adjustments:
Creative Co-op and Jamie Kay
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