Diono Radian 3QXT Ultimate 3 Across All-in-One Car Seat

Product Code: 51220-NA-01

Availability:In stock


Available Options


The Radian 3QXT model, is an elite standard convertible car seat. It's created with multiple layers of durable material, and a steel rebound bar, tested in the most rigid car crashes, for optimal safety. With 4 optional positions in booster or car seat configuration, weight capacity of 120 lbs, adjustable seat, head rest, and 5 point harness loops, it is bound to support endless years of safe travel. Its compact structure enables 3 seats to be aligned in a row, with guaranteed comfort. It also includes an extra newborn protective insert, cushioned harness pads, a soft liner, and a high wedge to keep your baby in a comfortable flat back position. To maintain cleanliness, the seat fabric easily removes for washing.


  • Fold flat for easy carrying & storage.
  • Certified for use on aircraft as they are FAA approved.
  • Easy click installation.
  • Newborn supportive inserts and a wedge enabling flat back position.
  • Anti Rebound bar along with 6 layers of durable protection for maximum safety.
  • Reinforced steel cup holder. 
  • Anti slip 5 point padded adjustable harness.
  • Installed technology absorbing pressure of abrupt stops.
  • Adjustable head rest, and expandable sides for maximum comfort. 
  • 4-50 lbs rear capacity to prolong safest travel position for infants.
  • 22-65 lbs forward facing.
  • 40-120 lbs Booster mode.
  • Maximum height 57".
  • Steel frame, high density plastic, polyester knit, EPP, EPS
  • Machine wash and dry.

Dimensions & Weight

  • 16" x 17" x 28" 
  • 25.8 lbs

Customer Reviews

No reviews yet

Order Processing & Shipping Estimates 

  • In stock items will be shipped within 2-7 business days.
  • Pre-order or special order items will have the estimated availability and/or shipping date mentioned on the product page.
  • Orders exceeding $74.99 (USD) are eligible for free shipping, all other orders will be a charged a shipping fee.


Return Policy

We at Mega Babies, pride ourselves with excellent customer service. We value our customers and want them to be pleased with their purchases. If for any reason you would like to return an item, Mega Babies offers a 30 day return policy with 100% money back guarantee. 


Return Shipping Address

Mega Babies USA
Att: Shipping Department
4309 14th Ave
Brooklyn, NY 11219


How To Process a Return

  • Please contact customer service by phone 718-437-3400 or via email Sales@megababiesusa.com.
  • Allow 1-2 weeks for returns to be processed. 


Return Conditions and Clarifications

  • Return Items need to be in unused and brand new condition, include all merchandise tags, and in the original packaging.
  • Please include the order number when processing a return. 
  • Clearance and reduced items are final sale.
  • Custom and specialty orders (furniture, mattresses, etc...) are non refundable.
  • Refund payment will be credited to the card used when purchased. 
  • Customer is responsible for return shipping fee.
  • Shipping cost is non refundable.
  • Items received as a gift, can be exchanged or eligible for store credit only.


Warranty Claims

We are here to guide you with any issues you have with items under warranty that malfunction and/or have defects. Unfortunately, we are not allowed to handle the claim directly. Claims need to be filed with the company. In any event you fail to reach the company, Mega Babies will try to intervene on your behalf.

Diono Radian 3QXT Ultimate 3 Across All-in-One Car Seat