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Diono® radian® 3QXT Ultimate 3 Across All-in-One Convertible Car Seat

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Diono® radian® 3QXT Ultimate 3 Across All-in-One Convertible Car Seat. View a larger version of this product image.
Diono® radian® 3QXT Ultimate 3 Across All-in-One Convertible Car Seat. View a larger version of this product image.


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about the product

The ultimate 3 across All-in-One car seat from birth to booster. Features 4 stages of complete newborn protection and all new Diono Safe+™ engineering to provide the next generation in car seat safety.
  • 5 ways to travel from birth to booster, the radian® 3QXT adapts as your child grows to offer a custom fit from birth up to 120 lb.
  • Rear facing mode:
    • Supports children up to 44" tall
    • Supports children from 4 lb. to 50 lb.
  • Forward facing with harness mode:
    • Supports children up to 57" tall
    • Supports children from 22 lb. to 65 lb.
  • High back belt booster mode:
    • Supports children from 44" to 57" tall
    • Supports children from 40 lb. to 120 lb.
  • 4 stage newborn protection:
    • Safe+™ newborn protection insert
    • Safe+™ newborn travel high wedge
    • Safe+™ 2-in-1 infant positioning liner
    • Safe+™ newborn harness pads for custom fit from birth
  • Keep your rear-facing child for longer with Diono Safe+™ protection; up to 50 lb
  • Safe+™ engineering radian® 3QX is subjected to a combination of the most rigorous crash tests
  • Built with radian® slim fit design to fit 3 across in most vehicles without compromising child or passenger comfort
  • Removable Safe+™ side impact management pod with 8 layers of interlocking energy-absorbing EPS/EPP foam, high density plastic and steel reinforcement combine to create ultimate side impact protection
  • Removable infant insert provides proper positioning and comfort
  • Slim fit design can fit 3 seats across in most vehicles
  • Safe+ anti slip harness pads
  • Safe+ 2-in-1 infant positioning liner
  • Safe+ steel anti-rebound bar for increased stability and reduced rebound rotation by up to 50%
  • Safe+ steel core frame
  • Safe+ easy adjustable position headrest
  • Comfort+ memory foam cushion and expandable sides
  • Folds flat
  • FAA-certified: convenient fold flat seat for aircraft use to take on trips
  • Superlatch™ connectors offers easy click installation system
  • Steel reinforced cup holder
  • Machine washable removable covers
  • Measures 16" D x 17" W x 28" H
  • Weighs 25.8 lb.
  • Certified for use in aircraft (harness mode only)
  • 2-year limited manufacturer's warranty
  • Imported
  • Model 51220 Black; 51221 Grey; 51223 Red; 51224 Blue; 51225 Purple; 51226 Yellow
  • skuId:



shipping & returns

Please be aware we've temporarily extended our delivery time frames due to Covid 19 precautions at our facilities. The extended time frames will be reflected in the estimated delivery date shown at checkout.

Free Standard Shipping on Orders Over $49. 

Free Standard Shipping with any online purchase of $49 or more (merchandise subtotal). Excluding store pick up items, gift cards, gift wrap charge, environmental handling fees, other applicable handling or administrative charges, and sales tax. Shipping surcharges on certain over-sized or heavy items still apply. These charges are indicated on the appropriate product information pages and will be displayed in the shipping subtotal of your order.

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