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Monterey® 4DXT Expandable Booster Seat [Black]

Monterey® 4DXT

The original 2-in-1 booster that grows with your big kid with SafePlus® Engineering

MSRP: $199.99
Was: $199.99
Now: $119.99
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The original 2-in-1 booster seat with one of a kind, easy-adjust, separate height and width expansion. Transforms from a high-back booster to a backless booster as your big kid grows. With 15 SafePlus® and style upgrades from the Monterey® 2XT.

This seat has been awarded Best Bet Booster by IIHS.

Features:

  • 8 Years One Booster - for your big kid from 40 - 120lbs (18-54 kg). It's all you will ever need.
  • Easy-adjust - 11-position headrest that grows up with your child. Engineered for safety and comfort with 2 layers of SafePlus® Side Impact Protection.
  • One of a kind - easy-adjust expandable backrest allows up to 6.5in (16.5cm) to grow with your big kid. With 2 layers of Side Impact Protection and deep padded cushioning.
  • Two built-in retractable 2-in-1 cup holder and snack tray - keeps your big kid's drink close at hand and stows away their essentials.
  • Our contoured premium soft fabrics - with layered foam padding that provide comfort and support can be easily removed for machine washing.
  • SafePlus® belt guides - easy access to seatbelt buckle help your big kid with self buckling - don't forget to check though!
  • Easy, quick and secure installation - engineered with automotive steel LATCH connectors and 2 easy adjust LATCH straps allow you to quickly tighten and secure your booster to your vehicle.
  • Engineered with side impact protection - our rigid shell is reinforced with 4 layers of high-impact aluminum and EPS energy absorbing foam, to protect the head, shoulders, and torso.
12 months standard warranty - extended to 36 months when you register with Diono® post purchase
What comes in the box?
Monterey® 4DXT Booster, Instruction Manual, Cup Holder
When is my child ready for a booster seat?
Diono booster seats can be used for children weighing 40-120 lbs. (18-54 kg) and are 38-63 in. (96.5-160 cm) tall. Typically once a child reaches 5 years of age they are mature enough to ride in a booster seat.
Which high back boosters have a detachable back?
Diono high back boosters with a detachable back are the Monterey® 4DXT, Monterey® 2XT, Cambria® 2. All come with a detachable back to convert into a backless booster seat.
Will the booster seat fit 3 across in my car?
Our booster seats fit 2 across in most cars. Each vehicle model is different and allows for various seating positions. Consumers should consult vehicle owners manual for appropriate car seat placement in their car that may fit more than 2 across.
Which booster seats come with cupholders?
Solana® has fabric cup holders. Solana® 2, Everett NXT, Cambria® 2, Monterey® XT, Monterey® 2XT, and Monterey® 4DXT have two retractable cup holders. Monterey® 5iST FixSafe® have a snap-in Monterey® cup holder.
Can you install the Monterey® 4DXT Latch with out latches?
The Monterey® 4DXT is recommended to be installed with the lower anchors if you vehicle is equipped with them. However, it can be used without.
Can I use them on flights?
Diono booster seats are not meant to be used on airplane. Boosters require a lap/shoulder belt and airplanes only have a lap belt.
When does my booster seat expire?
All Diono booster seats have a life span of 8 years, starting from the date you purchase your seat. In the event the date of purchase cannot be determined then we use the date of manufacture.
Do Diono's booster car seats work with Ford's inflatable seatbelts?
Please consult the seat manual. Diono Cambria and Monterey seats manufactured prior to 2017 can be used with Ford's inflatable seat belts. Newer models will not allow them to be used and will be stated in the car seat's manual.
Product Care:
Covers: Machine wash cold, line dry. Shell and Components: Spot clean
Minimum User Weight:
40 lb
Maximum User Weight:
120 lb
Maximum User Height:
63 in
Product Height:
27.2 in
Product Width:
20.5 in
Product Depth:
16.1 in
Seat Weight:
18.3 lb
Number of Head Support Positions:
11
product_faq_booster_inflatable_seatbelt:
Please consult the seat manual. Diono Cambria and Monterey seats manufactured prior to 2017 can be used with Ford's inflatable seat belts. Newer models will not allow them to be used and will be stated in the car seat's manual.

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