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Diono Monterey 5iST FixSafe High Back Booster Car Seat with Expandable Height and Width, Compact Fold to Full Size Booster, Foldable, Portable Booster for Go-Anywhere Travel, Black Jet

  • Based on 165 reviews
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Color: Black Jet


Features

  • EXPANDS IN HEIGHT AND WIDTH - One-hand automatic height and width adjustment provides 85percent more room as your child grows
  • COMPACT FOLD TO FULL SIZE BOOSTER IN SECONDS - 25percent smaller than the average booster seat without compromising safety or comfort
  • FIXSAFE RIGID LATCH CONNECTORS - Easy install with FixSafe rigid latch connectors for a safe and secure installation every time
  • 8 YEARS ONE BOOSTER - 12 headrest positions and expandable sides to grow with your child from 40 - 120 lb 18 - 54 kg (38 - 63 in tall 96 - 160 cm). Machine Washable fabric and convenient cup holder ensure your child's booster seat stays clean and comfortable
  • SAFE plus ENGINEERING - Includes 8 layers Safe plus side impact protection and rigorous crash testing to create the most advanced Monterey ever

Description

Introducing the next generation of expandable booster. Designed for ultimate portability, Monterey 5iST FixSafe transforms in seconds from a compact fold to a full-size booster seat, without compromising safety or comfort. At 25% smaller than the average booster, Monterey 5iST FixSafe folds down into a compact and convenient size and features an integrated carry handle and carry straps with designated storage compartment. So, whether youre on the daily commute, carpooling, storing in the garage or jumping in a cab, with Monterey 5 you can always take safety with you for the joy of the journey. Suitable from 40 - 120 lb Monterey 5iST FixSafe expands in height and width to provide up to 85% more room as they grow up to 63 tall. Featuring 12 headrest positions and expands up to 20 in width, Monterey 5iST FixSafe can adapt quickly to growing children, with plenty of room for shoulders, hips and legs. All of these great features have been combined with SafePlus engineering, with the Monterey 5iST FixSafe subjected to a combination of the most rigorous crash tests; front, rear, and side impacts, and rollover test to ensure the safest seat possible. The advanced SafePlus side impact protection features 8 layers of interlocking EPS and EPP foam and includes the SafePlus energy absorbing shell, to shield and protect with SafePlus airflow technology built in for optimum child comfort. The open design features easy to use SafePlus secure belt guides to eliminate misuse and SafePlus secure belt lock to ensure the adult seatbelt is always routed correctly. The seat base is contoured for child comfort and includes a cup holder for road trip drinks and snacks. Designed with a simple 4 step installation and adjustable rigid latch FixSafe connectors, Monterey 5iST FixSafe can be used straight out of the box, with no assembly required. When youre on the move or need to switch between vehicles, the FixSafe connectors offer a simple way to secure the booster to the vehicle latch system, for a safe and convenient installation every time.

Brand: Diono


Installation Type: Seat Belt


Material: Alloy Steel, Polypropylene, Plastic, Polystyrene


Color: Black Jet


Orientation: Forward Facing


Product Dimensions: ‎15 x 17 x 24.8 inches


Item model number: ‎15700


Minimum weight recommendation: ‎40 Pounds


Maximum weight recommendation: ‎120 Pounds


Minimum height recommendation: ‎38.2 Inches


Maximum height recommendation: ‎63 Inches


Material Type: ‎Alloy Steel, Polypropylene, Plastic, Polystyrene


Material Composition: ‎100% Polyester


Care instructions: ‎Covers Machine wash cold, line dry. Shell and Components Spot clean


Additional product features: ‎Transforms in seconds from a compact fold to a full-size booster seat, without compromising safety or comfort


Number Of Items: ‎1


Number of reclining positions: ‎12


Batteries required: ‎No


Orientation: ‎Forward Facing


Forward-facing minimum child weight: ‎40 Pounds


Forward-facing maximum child weight: ‎120 Pounds


Harness type: ‎Seat Belt


Is portable: ‎Yes


Item Weight: ‎18.7 pounds


Country/Region of origin: ‎China


Frequently asked questions

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Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Easy to install, safe and sturdy
Purchased this after a major car accident where my child was on another car seat that didn't quite perform as intended. This was purchased basef on safety reviews and like how easy it is to use. The seat is very sturdy, easy to snap in and remove, and more importantly, comfortable for my child. Perfect for traveling as it folds and can be stowed away in upper compartment of airplane. ... show more
Reviewed in the United States on February 10, 2024 by JAG

  • Easiest install ever
This booster is not only nice to look at but it's comfortable. The seat doesn't have as much padding on the bootie as our old seat but he doesn't mind. The fixsafe latch system was a bit hard to get to pop out at first , I had to really push the button extremely hard to get them to come out. But then the install was a breeze. So easy. The chair itself is quite light which makes it convenient to put in other cars if necessary, it folds completely into itself and makes for very easy travel. It could easily fit in an overhead compartment on an airplane and it comes with straps to wear it on your back as a " back pack ". The cup holder is bigger to accommodate bigger cups and it's easy for my son to put the belt on himself. Overall I'm really happy w my choice. We are a diono family and when my old one was compromised from an accident it was a no brainer I was getting another Diono. We upgraded from a Rainier to the Monterey since my son is getting bigger and taller this seat accommodates up to 63 inches and 120 lbs. So he can be in it longer. Which was a big appealing factor in the decision. ... show more
Reviewed in the United States on October 15, 2021 by Kelly

  • Diono Great child car seat
Just bought and received my third seat. My 3 and I love these car seat. Easy to install and portable, which was major part in my decision making. Every time we get in or out of the car at least 1 of my 3 children are raving how much they love their Diono car seat.
Reviewed in the United States on August 25, 2023 by Darryl E. Bonner

  • Fits in a Tesla Model 3
We are another Tesla Model 3 family frustrated when our car seat that was supposed to easily convert from a harness to a belt positioner ended up being too wide to access the seatbelt buckle in that mode. Apparently this new model of the Diono Monterey and the Diono Everett are two of a very few models of high back boosters that are narrow enough to make the buckle accessible. I went with this one because it looks cool and in case we wanted to travel with it. However, we did still have to buy a 3” rigid seatbelt extender to get the buckle out from recessed so that my child can buckle it herself. My engineer husband was not as concerned about safety of using the extender as I was, but in the end an easily buckled child is safer than one where it’s hard to tell if the buckle has clicked because you need an adults weight on it to make it click. I think the Everett is 0.5” narrower and that may make all the difference and I probably could’ve returned this to get that one. Anyway, so far so good in terms of its comfort, my almost 6 year old (46” and 52 lbs) has fallen asleep in it a couple evenings already. She used to get car sick when rear facing, and we went on a 2 hour road trip this past weekend and she had no issues (I still have blue emetic bags stacked everywhere, though!). It installed fairly easily and feels rock solid due to the rigid latch. There are no arm rests but I don’t think my daughter cares since the previous car seat didn’t really have them. The cup holder does the job and fits her wider Contigo and stainless steel water bottles. We also got the Diono brand cubby/box for her to keep snacks, books, sunglasses, etc. because her old Chicco MyFit had a little box that attached that she got used to having it all close. So far no issues getting her to sit up straight and not fool around with the adult belt on…if we had switched her to this mode a few months ago that wouldn’t have been the case. Much safer in a harness as long as possible, but this one is good when your child is finally ready! ... show more
Reviewed in the United States on September 26, 2022 by ebindc

  • Good option for travel, save your $$ if just daily use
We chose this model for the compact fold/straps because we were planning plane travel with driving on the other end for our 5yo who is not mature enough for a bottom seat only booster for any significant distance. The fold is great and compact. The provided straps are just webbing, and There was no way we’d use them for more than a minute. I found some clip on backpack straps on Amazon that were more comfortable, but it sits at an awkward angle. You’re better off using some bungee cords to strap it to the handle of rolling luggage if you’re going very far. We gate checked it for our flights but you may be able to put it in an overhead bin. Since the back does not detach, it’s easy to quickly install and remove from an Uber. I had trouble getting the isofix latch connectors to work in one Uber (Toyota sienna, I believe) but it was a short ride so we went without them completely attached. We also like that the sides of this seat expand like the other Monterey models because my son is tall with a long and wide torso and would likely have cramped shoulders by the time he ages out of a standard booster seat. What I didn’t realize until we got it is that the width expands as you raise the headrest, not independently like the other models. Overall we like it but unless you’re planning some travel that includes Ubers and/or flights where you’ll rent a car or ride with family/friends on the other end, save your $$. We have the $100 XT model in our other car and it functions just as well if you’re installing it once and leaving it there (and it still has the expandable back panel). If your child is average height/weight/build, you can pick something even cheaper. ... show more
Reviewed in the United States on August 18, 2021 by AK

  • Awesome
Now my big lil kid can hit 3Gs in the sharp corners safely
Reviewed in the United States on December 23, 2023 by Brian

  • Best comfort.
Color: Gray Slate
My kid loved this seat. It is extremely confortable for him.
Reviewed in the United States on July 19, 2022 by Julie Lopez

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