| Mode | Weight | Height |
|---|---|---|
| Rear-facing harness | 4–50 lb | 18–44 in |
| Forward-facing harness | 22–65 lb | 30–57 in |
| Belt-positioning booster | 40–120 lb | 40–57 in |
- Seat weight
- Not published
- Width
- Not published
- Usable life
- 10 years
- Aircraft
- Certified
Diono does not sell this seat on Amazon. See its own site for photos.
Diono Radian 3R SafePlus All-in-One Convertible Car Seat
An all-in-one car seat with 3 modes: rear-facing harness 4 to 50 lb, 18 to 44 in; forward-facing harness 26.5 to 65 lb, 30 to 57 in; belt-positioning booster 40 to 120 lb, 40 to 57 in.
At a glance
- Fits children from 4 to 120 lb
- Up to 57 in tall
- 3 modes: rear-facing harness, forward-facing harness, belt-positioning booster
- 10-year usable life
- Certified for aircraft use
Not sold on Amazon
Diono lists this seat on its US site. Buy from Diono or an authorized retailer, and confirm the exact model number before you buy.
Who is the Radian 3R SafePlus All-in-One Convertible Car Seat for?
The Radian 3R SafePlus is an all-in-one car seat: rear-facing from 4 to 50 lb and 18 to 44 in, forward-facing with the harness from 26.5 to 65 lb and 30 to 57 in, then a booster from 40 to 120 lb. Diono lists it at 17 in wide and 32 lb, and it expires 10 years after purchase.
Reasons to consider it
- A 17 in width, with 51 in between door handles needed for 3 Radian models across
- Rear-facing to 50 lb or 44 in, with a detachable rear-facing base
- A level line for rear-facing without the base when an elevated seat bight gets in the way
- Aircraft use in harness mode, and a seat that folds and straps closed
Things to weigh up
- Children under 26.5 lb or under one year old must stay rear-facing
- The manual requires the top tether forward-facing, while a Diono support page calls it recommended in the US; I would follow the manual
- Diono lists the seat at 32 lb
- The manual says the anti-rebound bar or panel, comfort insert and SIM pod come only with select models, without naming which
My take on the Radian 3R SafePlus All-in-One Convertible Car Seat
The 3R SafePlus suits a family that wants a narrow all-in-one seat and long rear-facing; Diono gives 51 in between door handles as the minimum for 3 Radian models across. Its manual sets a 26.5 lb forward-facing minimum and requires the top tether forward-facing. The 3RXT SafePlus shares the same universal manual and limits, and Diono lists it at 30.6 lb with the same 17 in width.
A research summary of Diono’s published specifications and manual, read . Not a hands-on test or a crash-safety rating.
Who the Radian 3R SafePlus All-in-One Convertible Car Seat fits
This seat covers 3 stages, and a child has to meet every limit of the stage they are in. Diono gives it a 10-year life from the date of manufacture, so check the date label before using a hand-me-down.
- Rear-facing harness4 to 50 lb · 18 to 44 in
- The child faces the back of the car, which keeps the head, neck and spine supported in a frontal crash. Keep this mode as long as the child fits it.
- Forward-facing harness26.5 to 65 lb · 30 to 57 in
- The child faces forward in the seat’s own harness. Use the top tether every time, and stay in the harness until the child outgrows it.
- Belt-positioning booster40 to 120 lb · 40 to 57 in
- The seat raises the child so the vehicle’s own lap and shoulder belt sits on the hips and across the shoulder. The child has to sit properly for the whole ride.
What are the Radian 3R SafePlus All-in-One Convertible Car Seat weight, height and age limits?
| Mode | Child weight | Child height | Minimum age | Conditions |
|---|---|---|---|---|
| Rear-facing harness | 4 to 50 lb | 18 to 44 in | Not published | LATCH installation limited to 35 lb |
| Forward-facing harness | 26.5 to 65 lb | 30 to 57 in | Not published | 26.5-30 lb must use the middle buckle slot |
| Belt-positioning booster | 40 to 120 lb | 40 to 57 in | Not published | — |
A child must meet every limit for the mode they use. The labels on your seat and its manual are the final word.
Radian 3R SafePlus All-in-One Convertible Car Seat specifications
- Seat weight
- Not published
- Width
- Not published
- Usable life
- 10 years
- Aircraft use
- Certified for aircraft (see manual for which modes)
Will it fit your car?
Diono does not publish a width for this seat, so measure your back seat and compare it with the seat in a store before buying.
- Check your vehicle manual for lower anchor positions and any head-restraint rules.
- Rear-facing seats need front-seat room: try the install behind the driver before you commit.
- Certified for aircraft use, so it can travel as a seat rather than checked baggage.
What to know before you live with it
Rear-facing installation
Rear-facing covers 4 to 50 lb and 18 to 44 in, with the harness at or below the shoulders and the top of the head at least 1.5 in below the shell. Diono recommends the detachable rear-facing base. Its feet tuck into a flat seat bight, but should not be pushed into an elevated one; if the base cannot be installed well there, the manual suggests removing it and using the blue level line instead. LATCH is allowed to 35 lb, then a locked seat belt to 50 lb. The seat should move less than 1 in at the rear-facing belt path, and the adjustable bottom is not used rear-facing.
Forward-facing: tether, SafeStop and buckle
Forward-facing with the harness covers 26.5 to 65 lb and 30 to 57 in, and children under 26.5 lb or under one year old must ride rear-facing. The manual requires the top tether. The adjustable bottom must always be lowered forward-facing. The SafeStop attaches to the harness for children from 26.5 to 40 lb and comes off at 40 lb. From 26.5 to 30 lb the buckle uses the middle slot, and above 30 lb the forward-most slot. LATCH is allowed to 40 lb. The top of the seat must be supported by the vehicle head support or seat back.
Headrest, booster mode and outgrowing it
With harness slots 1 to 2, the headrest sits level with the top of the seat; with slots 3 to 5, its bottom edge sits above the shoulders, level with the jaw. Booster mode covers 40 to 120 lb and 40 to 57 in with the harness removed, the shoulders at or above the 4th slot, and only the vehicle lap/shoulder belt. The manual says the child is too tall when, forward-facing, the tops of the ears are above the seat back, the shoulders touch the headrest at its highest setting, or the child is over 57 in.
Cover removal, washing and folding
The parts list includes a Diono Cover Tool to help refit the cover. To remove the cover, take off the headrest cover, remove the harness, buckle and buckle pad, unfasten the snaps under the headrest, release four plastic tabs under the seat bottom, then pull the fabric out of the shell channel. Take the memory foam out first, because it is not washed. The seat cover, comfort insert, buckle pad and harness pads are machine or hand washed in cold water on a gentle cycle with mild detergent and dried flat out of direct sunlight, with no bleach, ironing or dry cleaning. The harness straps are spot cleaned only. To fold, pull the red release levers and fasten the red carry strap.
Is the Radian 3R SafePlus All-in-One Convertible Car Seat recalled?
- 17C003000: does not cover this model. The Part 573 report for campaign 17C003000 lists six models only: Radian R100 (model no. 16600 or 16000), Radian R120 (16800 or 16000), Radian RXT (16900 or 16000), Olympia (30100), Pacifica (30400 or 300000) and Rainier (30300 or 300000), built between November 25, 2013 and September 5, 2017. The Radian 3R SafePlus is a separately named Radian 3 series seat and is not among the listed models. Campaign source (read ).
Each campaign naming this family was read against this model’s numbers and build dates, and none covers it. Still check your seat’s model number and date of manufacture before use, especially on a used seat.
Radian 3R SafePlus All-in-One Convertible Car Seat: common questions
How wide and heavy is the Radian 3R SafePlus?
Diono lists it at 28.5 in tall, 17 in wide and 16 in deep, with a seat weight of 32 lb. Folded, the depth is 11.5 in.
Is the top tether required on the Radian 3R SafePlus?
The manual says Diono requires the top tether on a forward-facing car seat, and repeats this in the booster section. I would confirm the seating position has a tether anchor before buying.
Diono Radian SafePlus Series universal manual (PDF) (opens in a new tab)
Can the Radian 3R SafePlus fit 3-across?
Diono gives a minimum of 51 in of vehicle seat width between the door handles to fit 3 Radian models across.
Diono: Radian 3R SafePlus 3-across space (opens in a new tab)
How much front-to-back room does it need rear-facing?
Diono says a rear-facing 3R SafePlus uses 30 to 36 in between the vehicle's back seat and the back of the front seat, depending on seat shape and contour.
Diono: Radian 3R SafePlus rear-facing room (opens in a new tab)
Can I use the Radian 3R SafePlus on a plane, and when does it expire?
The manual says it is certified for aircraft only in harness mode, not as a booster, because aircraft seats have no shoulder belts. It expires ten years from the date of purchase.
Diono Radian SafePlus Series universal manual (PDF) (opens in a new tab)
How is the Radian 3RXT SafePlus different?
Diono lists the 3RXT SafePlus at 28.5 in tall, 17 in wide and 16 in deep, with a seat weight of 30.6 lb. It shares the same universal manual and limits.
Diono Radian 3RXT SafePlus support page (opens in a new tab)
Answers refer to the model and manual version on this page. Check the instructions supplied with your seat.
Before you buy
- Weigh and measure your child. The limits above are the manufacturer’s, and a child has to meet all of them for the mode they will use.
- Confirm the exact version. Colors, retail exclusives and model numbers change limits more often than you would expect.
- Read the manual before you buy, not after. It is linked above and holds the fit rules, the install methods and the expiry.
- Check recalls by model number and date of manufacture, and register the seat with Diono so you hear about the next one.
Sources
- Diono US product page
- Radian_SafePlus_Universal_Manual_English.pdf
- diono.zendesk.com/hc/en-us/articles/32665533889171-Radian-3R-SafePlus-Manual
- Diono Radian SafePlus Series universal manual (PDF)
- Diono Radian 3R SafePlus support page
- Diono: Radian 3R SafePlus dimensions
- Diono: is the top tether required on the Radian 3R SafePlus
- Diono: Radian 3R SafePlus 3-across space
- Diono: Radian 3R SafePlus rear-facing room
- Diono Radian 3RXT SafePlus support page
- NHTSA car seat guidance
Other Diono convertible car seats
| Model | Top child weight | Seat weight | Width | Usable life |
|---|---|---|---|---|
| Radian 3R SafePlus All-in-One Convertible Car Seat (this seat) | 120 lb | — | — | 10 years |
| Radian 3QX SafePlus All-in-One Convertible Car Seat | 120 lb | — | — | 10 years |
| Radian 3QXT SafePlus All-in-One Convertible Car Seat | 120 lb | — | — | 10 years |
| Radian 3QXT FirstClass SafePlus (Radian 3QXT+) All-in-One Convertible Car Seat | 120 lb | — | — | 10 years |
| Radian 3RXT SafePlus All-in-One Convertible Car Seat | 120 lb | — | — | 10 years |
| Radian 3RXT SafePlus Max All-in-One Convertible Car Seat | 120 lb | — | — | 10 years |
| Radian 3R All-in-One Convertible Car Seat | 120 lb | — | — | 10 years |
| Radian 3RX All-in-One Convertible Car Seat | 120 lb | — | — | 10 years |
| Radian 3RXT All-in-One Convertible Car Seat | 120 lb | — | — | 10 years |