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Diono RadianRXT

The Diono RadianRXT has now been discontinued and replaced with a new model the Radian 3RXT.

This is another great seat that can fit 3-across in most cars. It has also been getting good reviews from satisfied parents.

4.4 out of 5 stars (4.4 / 5)

Diono Radian3RXT at Amazon >>

The Diono RadianRXT is a 3-In-1 type of convertible car seat that can be used for your child from 5 Pounds all the way up to 120 pounds. The seat has a shelf-life of 10 years.

Initially, the Radian RXT is used rear facing from 5 to 45 pounds. It then converts to front facing complete with 5-point harness suitable for a child of 20 to 80 pounds. Finally, the harness can be removed, and it can be used as a belt-positioning booster suitable for use from 50 to 120 pounds.

This model is constructed using a very strong steel alloy frame together with aluminum reinforced sides. This frame is then generously covered with energy absorbing EPS foam to give wrap round protection to your child in the event of an accident. Memory foam is also used for an extra comfortable ride.

The 5-Point Safestop® Energy-Absorbing Harness System is fully adjustable with 5 shoulder and 3 buckle positions so you can be sure of achieving a good fit. The head support also has 12 different height adjustments, so there is plenty of adjustment for a growing child. The RadianRXT also comes complete with infant body support cushions that can be removed as your child gets bigger. In the forward facing position the seat can be reclined in 2 different settings for added comfort.

Installation can be accomplished by using either the LATCH system up to 80lbs, or your own vehicle safety belts. This is a narrower model than some on the market and it is possible to fit 3 Seats Across on most mid-size cars. So, if you are struggling with seating 3 children then the RadianRXT could be the solution.

This seat can also be folded flat when not being used or for easy transporting.

The manufacturer, Diono, offers a one year limited warranty.

The RadianRXT comes in several different designs including Black Cobalt, Plum, Shadow and Oyster. The covers can be removed for machine washing by following the manufacturer’s comprehensive instructions.


3-in-1 Convertible  Seat (Rear Facing/Front Facing/Belt Positioning Booster)

Used Rear Facing
Child Weight:
from 5 to 45 Pounds

Used Front Facing with Harness Attached
Child Weight: from 20 to 80 Pounds

Used Front Facing as a Belt-Positioning Booster

Child Weight: from 50 to 120 Pounds

Height Open: 28.5 Inches
Width Open: 17 Inches
Depth Open: 16 Inches
Height Folded: 28.5 Inches
Width Folded: 17 Inches
Depth Folded: 10 Inches
Weight: 24 Pounds


  • Excellent Side Impact Protection
  • Diono patented Safestop® Energy-Absorbing Harness System
  • Can be used with LATCH system up to child weight of 80lbs
  • Can fit 3 seats across in some mid-sized vehicles
  • Adjustable head support has 12 separate positions
  • 2-position recline when used forward facing
  • Infant support cushions supplied
  • Folds flat for easy transport and storage
  • Cup Holder

What Parents Liked about It..

  • Excellent crash test ratings
  • Folds for carrying
  • Narrower than most other 3-in-1 models
  • Sturdy
  • Made from quality materials

What the Parents Didn’t Like..

  • Very heavy to carry
  • It can be difficult to install

Review Summary

The RadianRXT received great reviews from the majority of parents. It particularly impressed with its sturdy build quality and the use of top-quality materials. The thoughtful design also placed it head and shoulders above other 3-in-1 convertible seats.

There were a couple of criticisms; it was thought to be heavy at 25lbs and in addition, some parents said that they had some difficulties getting it installed properly.

The seat is without doubt a great quality, all-in-one solution for seating your child safely in the car right up to 120lbs. Also, if you need to install 3 seats across the back seat of your car then the RadianRXT is a definite contender.

The RadianRXT is a Recommended Buy.

Make sure that you get your’s from a reputable seller such as Amazon who offer a “No Quibble” Returns Policy if you should experience any difficulties.

See the Diono Radian 3RXT at Amazon

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