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Diono Radian 3 QXT Convertible Car Seat

Diono Radian 3 QXT Convertible Car Seat

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Product details
Official manufacturer description


The ultimate 3 across All-in-One car seat from birth to booster (4 - 120 lb) Featuring advanced 4-in-1 newborn protection and all new Safe+® engineering to provide the next generation in car seat safety.


  • THE ULTIMATE RADIAN ALL-IN-ONE CONVERTIBLE CAR SEAT - From infant to booster seat, rear and forward facing the Radian® 3QXT adapts as your child grows for 10 years of use (4 - 120 lb).
  • 4-IN-1 NEWBORN PROTECTION - Designed for safe rear facing travel from 4 - 50 lb complete with Safe+® inserts and Safe+® steel anti-rebound bar to reduce rebound rotation by 50%.
  • SAFE+® ENGINEERING - Our most rigorously tested Radian® all-in-one convertible car seat; featuring Safe+® steel rear facing anti-rebound bar, steel reinforced frame, advanced side impact protection and diono SuperLATCH attachment.
  • SLIM FIT DESIGN FOR 3 ACROSS - Features 8 layers of Safe+® side impact protection (including Safe+® side Impact management pod 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.
  • THE ORIGINAL RADIAN® 3 ACROSS: Built with our famous Radian® slim fit convertible design for a 3-across option only with Diono Radian® combinations, without compromising child or passenger comfort. Feel safe having your children secure in the backseat.
Product dimensions
16 in. D x 17 in. W x 28 in. H
Product weight
25.8 lbs
Head rest positions
Installation Type
Rigid Latch System
TSA Approved
Model year
Recommended Age Range
From newborn up to 10 years
Child Maximum Weight (Forward Facing)
65 lbs
Child Maximum Weight (Booster)
120 lbs
Child Maximum Weight (Rear Facing)
50 lbs
Child Maximum Height (Booster)
57 in.
Child Maximum Height (Forward Facing)
57 in.
Child Maximum Height (Rear Facing)
44 in.
Child Minimum Weight (Rear Facing)
4 lbs
Child Minimum Height (Booster)
44 in.
Child Minimum Weight (Booster)
40 lbs
Child Minimum Weight (Forward Facing)
22 lbs
Care instruction
Covers: Machine wash cold, line dry. Shell and Components: Spot clean
Folded dimensions
11.5 in. D x 17 in. W x 28 in. H
Height range
Up to 57.1 in.
Steel, Plastic, Aluminum, Textile
Recline positions
Weight Range
4 to 120 lbs
Diono Radian 3 QXT Convertible Car Seat
Recommended by Curated experts

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Top reviews
Would an expert recommend this for your baby?
Gregg Mason
Gregg Mason
Verified baby & toddler expert
Reviewed Aug 8, 2022

From 4- 120 pounds this option is one of the most popular, safest, and comfortable options that expands for children's growth and orientation. Features one hand easy adjust of the headrest, great for tight spaces, and is narrow for a three across install for a growing family in the backseat.

Kristina Spencer
Kristina Spencer
Verified baby & toddler expert
Reviewed Aug 25, 2022

Fits kids from 4 - 120 lbs all the way up to a booster seat! Slim fitting, designed for 3 across. Cup holder, adjustable headrest, and side impact protection.