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Infant Car Seat Fit Guide

Buckle up and enjoy the ride through life’s greatest adventure — parenthood. From the first drive home all the way to school carpools, our family of car seats will be there to grow with yours. From choosing the right seat to knowing when it’s time to transition, we’re here to guide you every mile and milestone! Here’s everything you need to keep your child safe, secure, and supported every ride.

Infant Car Seats

The headrest and harness for added security

Headrest + Harness

The headrest and harness work together to ensure a secure fit. Adjust the headrest so the harness slots are at or just below the shoulders. The harness should lie flat and pass the pinch test — snug with no slack.

Headrest + Harness How-To

The chest clip is located at the top of the harness

Chest Clip

Positioned at armpit level, the chest clip keeps the harness in place and helps prevent ejection in a crash. It should rest over the child’s collarbone and align with the snug harness for the safest pre-crash positioning.

Chest Clip How-To

Illustration highlighting the crotch buckle on the harness

Crotch Buckle

The crotch buckle should sit flat against the child without gaps or slack. It must not be under the child or too far forward.

Crotch Buckle How-To

The infant insert fits within the car seat

Infant Insert

Designed for babies 4–11 lbs, the infant insert provides vital support for the head, neck, and hips. We’ll help you identify when your baby needs it — and when it’s time to remove it for optimal comfort and fit.

Aria Infant Insert How-To

Mesa Infant Insert How-To