Car Seats
for children 22-120 lbs. / 1 - 12 years

ADVANCED Transitions 3-in-1 Combination Booster Car Seat (Mercury)


Sheathed in moisture-wicking piqué-knit fabric, and three layers of pressure-reducing Comfort Tech™ padding, this combination car seat will provide your child with premium comfort throughout their booster years.


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Item No. 34421686

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Additional Information

The last car seat you'll ever need...

The Transitions 3-in-1 combination seat has three forward-facing modes that will accomodate your child through their booster-seat years. As a harness, highback, and a no-back booster, the Transitions car seat gives parents with older kids a one-seat-fits-all booster seat solution.

Child Specs (22-120lbs.)


  • Weight: 22 - 65 lbs. (10 - 29.4 kg.)
  • Height: 28 - 50 in. (71–127 cm.)
  • Age: The child is one year old or older
  • Fit: The tops of child’s ears are at (or below) the top of the child restraint headrest.


  • Weight: 40 - 120 lbs. (18 - 54.4 kg.)
  • Height: 44 - 57 in. (112–145 cm.)
  • Age: combination-sb-age
  • Fit: combination-sb-fit


  • Weight: 40 - 120 lbs. (18 - 54.4 kg.)
  • Height: 44 - 57 in. (112 - 145 cm.)
  • Age: At least four years old
  • Fit: Ears below the top of the vehicle seat headrest.

Product & Shipping Specs

  • Package Width: 20
  • Package Weight: 24
  • Package Depth: 20
  • Package Width: 20

Safety Testing

At Evenflo, we continue to go above and beyond government standards to provide car seats that are tested at 2X the Federal Crash Test Standard.

  • Side Impact Tested: Meets or exceeds all applicable federal safety standards and Evenflo’s side impact standards.
  • Designed and tested for structural integrity at energy levels approximately 2X the federal crash test standard.
  • FMVSS 213: Federal Motor Vehicle Safety Standards for Child Restraint Systems
  • FMVSS 302: Federal Motor Vehicle Safety Standards for Flammability of Interior Materials
  • CMVSS 302: Canada Motor Vehicle Safety Standard
  • CMVSS 213: Canada Motor Vehicle Safety Standard
  • Certified For Use In Aircraft: When used with the internal 5-point harness this restraint meets FAA Inversion requirements for airplane use.
  • Evenflo Temperature Testing: All current Evenflo car seats are tested for product integrity at both high and low temperatures.

Use & Care

Read all instructions and warnings on the product, product labels, and instruction manuals before use. Consult your vehicle owner’s manual to determine proper placement of child restraint in your vehicle and familiarize yourself with your vehicle’s components.

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Cleaning Instructions
  • DO NOT lubricate or immerse in water any part of this child restraint, unless rinsing is permitted
  • Plastic and metal parts may be wiped clean with mild soap and water and dried with a soft cloth. Do not use abrasive cleaners or solvents.
  • Take care not to damage any labels.
  • The harness can be wiped clean with mild soap and water. Allow harness to air dry.
  • Machine wash the seat pad separately in cold water, delicate cycle. Tumble dry 10 to 15 minutes on low heat.
  • Periodically inspect and clean the restraint's crotch buckle of food, liquids, and other debris to ensure proper latching. Place the buckle in a cup of warm water and gently agitate the buckle back and forth. Press the red button several times while the buckle is in the water. Do not submerge the harness strap. To avoid damage to the buckle, do not clean the buckle with soap or detergents and do not use a lubricant.