Diono Car Seats: What's the Difference?

What's the difference?

Your child's protection is so important, which makes buying a convertible car seat a huge decision. Diono offers a wide range to chose from, and you may be asking, "What's the difference?" - well, West Coast Kids is here to help!


Radian® R Series

First, let's break down the 3 convertible car seats in the Radian® R Series. We'll start wih the Radian 3R, which is the most basic option Diono offers. From there, the models build on the features listed below.


Radian® 3R includes:

  • Rear facing weight limit: 5-50 lbs
  • Forward facing weight limit: 22-65 lbs
  • Belt positioning booster weight limit: 40-120 lbs
    • Reinforced steel core for extra protection, and memory foam for extra comfort
    • Strong but slim design, ideal for 3-across installs in most vehicles
    • Covers that can be removed for easy washing and drying
    • A 10-year expiration date form the date of purchase (WOW!)
    • FAA approval for use on an aircraft in harness mode

Radian® 3RX includes:

  • All the features included with the Radian® 3R, PLUS: 
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    • The head support liner which is perfect for your child if they do not have full head support
    • The cup holder for your child who loves t have their drink on the go

Radian® 3RXT includes:

  • All the features included with the Radian® 3R, PLUS: 
    •  
    • The head support liner which is perfect for your child if they do not have full head support
    • The cup holder for your child who loves to have their drink on the go
    • Includes a 12 position headrest with adjustable wings for maximum comfort on those longer road trips
    • Includes a rear-facing wedge which is ideal for newborns to allow for proper breathing and head angle
    • 2-in-1 infant positioning liner
    • Side impact tested for optimum safety and protection

Radian® 3RXT Safe+ includes:

  • All the features included with the Radian® 3RXT, PLUS: 
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    • Includes Safe+® steel anti-rebound bar which reduces rebound rotation by up to 50% for extending rear-facing travel up to 50 lb
    • Easy-access side storage for harness cleaning and replacement
    • Deeper side walls for enchanced SIP (Side Impact Protection)
    • Improved headrest with an easy one hand adjustment, with 22% increase in range over the RXT headrest
    • Safe+® enhanced testing for side impact and rollover
    • An XL cup holder to grow with your little one

Radian® Q Series

Diono Q-Series car seats are a newer line and includes Radian 3QXT+ and the Radian 3QX. The most notable differences between the Q-Series and R-Series car seats is the premium fabric used, the redesigned headrest for ultra comfort, deeper sidewalls for those longer road trips, and the Q line can be used with your little one from as early as 4 lbs up to 120 lbs. Ultimately, the Q-Series is luxury for your little one, and we break down the features an why you'll love the two car seats in the series:


Radian® 3QX includes:

  • Rear facing weight limit: 4-50 lbs
  • Forward facing weight limit: 22-65 lbs
  • Belt positioning booster weight limit: 40-120 lbs
    • Safe+® steel rear-facing anti-rebound bar, steel reinforced frame, advanced side impact protection and Diono SuperLATCH attachment.
    • Features 6 layers of Safe+® side impact protection without compromising 3 across installation in most midsize vehicles
    • One hand easy adjust 12 position headrest - Contoured to improve child head containment and provides a 22% increase in occupancy range from the Radian® R series

Radian® 3QXT Safe+ includes:

  • All the features included with the Radian® 3QX, PLUS:
    • Safe+® 2-in-1 anti-rebound panel that enhances rear-facing safety and comfort
    • Adjustable calf support provides additional comfort as they transition to forward-facing
    • Safe+ engineering - Features a unique combination of engineering features and testing to the highest safety standards to ensure we have the safest seat possible
    • Exclusive premium fashion – Designed with airflow mesh panels and premium fabrics. Easy remove and machine washable for comfort, convenience and style All-in-One
    • Slim fit 3 across - Ultimate passenger comfort with spacious design but only 17” wide to fit 3 across in most midsize vehicles.
    • Includes 2x XL Cup holders & Car Seat Protector

Diono Angle Adjuster

Lastly, we must make note of the Angle Adjuster, which should absolutely be purchased in conjunction with any Diono convertible car seat.

The Angle Adjuster positions rear-facing Diono convertible car seats at a more upright angle for older children and can add up to 4” more room behind the front seats for more front leg room. The dense foam construction adds firm, lateral support for increased stability and fits all Diono Convertible car seats. Trust us, this is a game changer when you’re buying any Diono convertible car seat!