COMING SOON! Monterey® 5iST FixSafe® Booster

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COMING SOON! Designed for ultimate portability, the Monterey® 5iST FixSafe™ transforms in seconds from a compact fold to a full-size booster seat, without compromising safety or comfort. Suitable from 40 – 120 lbs and up to 63″ tall. COMING SOON!

  • Expands in height and width to provide 85% more occupancy
  • Compact fold with built-in carry straps
  • 8 Layers of Safe+ Side Impact Protection
  • 12-position headrest
  • Safe+ Energy Absorbing Shell
  • Safe+ Secure Belt Lock and Belt Guides
  • FixSafe Rigid LATCH Connectors
  • Designated Storage Compartment
  • Removable Cup Holder

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SafePlus™ Engineering

Featuring SafePlus™ engineering, the Monterey® 5iST FixSafe™ has been subjected to rigorous crash testing to create the most advanced Monterey® ever.

Room To Grow

Featuring 12 headrest positions and expands up to 20” in width, the Monterey® 5iST FixSafe™ provides to 85% more room and can accomodate children up to 63” tall.

Travel Friendly

At 25% smaller than the average booster, the Monterey® 5iST FixSafe™ folds down into a compact and convenient size. The integrated carry handle and straps also make it ideal for travel and provides 3 ways to carry.

Machine Washable

The Monterey® 5iST FixSafe™ is machine washable and features easy remove covers.

Product Specs

Available Colors

Black Jet, Blue Sky, Gray Slate, Purple Plum, Red Cherry, Yellow Mineral

Product Weight 18.7 lbs.
Product Dimensions 15 x 17 x 24.8 inches

Additional Info

Dimensions (Folded) 7.5 x 17.9 x 23.4 inches
Minimum User Weight 40 lbs
Maximum User Weight 120 lbs
Maximum User Height 63 inches
Head Support Positions 12
Cup Holder Yes
Use and Care ‎Covers: Machine wash cold and line dry. Shell and Components: Spot clean
Warranty 12 months standard warranty - extended to 36 months when you register with Diono® post purchase
  • What comes in the box?

    Monterey® 5iST FixSafe™ Booster, Instruction Manual, Cup Holder, Carry Strap x2

  • Diono booster seats can be used for children weighing 40-120 lbs. and are 38-63 in. tall. Typically once a child reaches 5 years of age they are mature enough to ride in a booster seat.

  • 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.

  • Press the LATCH release button on the front of the booster. Attach the LATCH connectors to the vehicle’s lower anchors. Confirm the connector’s lock indicator changes from red to green. Push the seat backward until it touches the vehicle seat back.

  • Press the LATCH release button located on the front of the car seat and pull the car seat away from the vehicle backseat.

  • Yes, it can be used without the LATCH. They will need to use the shoulder seat belt to hold the seat in place when not in use to prevent it from becoming a flying object during a crash or sudden stop.

  • Locate the straps included with the car seat accessories. Attach the straps to the fabric loops on the back of the seat. Next adjust the straps for comfort before use.

  • 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.