Layette lists and registry guides give new parents a decent sense of a newborn’s needs. But what happens when the little nuggets phase out of that first round of purchases? Our new “Product Evolution” newsletter series addresses the various gear stages for the baby-through-toddler years—starting today, with car seats. Gear expert Jamie Grayson (The Baby Guy NYC) gave us the lowdown:

Phase One: Infant Seat
Recommended models: Graco Snugride 35, Cybex Aton, Chicco KeyFit 30 and Britax Chaperone
Details: Infant seats (which you can easily spot by their carry handles) are always rear-facing, and usually have weight parameters of 5 to 22 pounds, although some now begin at 4 pounds (great for low birth weight babies) and go up as high as 35 pounds. The harness in a rear-facing seat should rest at or below an infant’s shoulders, and should be tightened enough so that you can only fit one finger between the baby and the harness.
When to graduate: Many people think that if a baby’s legs hang off the seat’s edge, it’s time to move on to the next car seat. Incorrect. Your baby can ride in an infant carrier until the top of her head rests one inch below the top of the car seat shell. Once that happens, or once she reaches the weight limit, it’s time to buy a convertible seat.

Phase Two: Convertible Seat
Recommended models: Britax Marathon, Safety First Complete Air 65, Sunshine Kids Radian 80 SL
Details: A convertible seat can be both rear- and forward-facing. (Be sure to take notice of your seat’s rear-facing weight limit.) When you do flip him around to forward-facing, the straps on the harness should rest at or above his shoulders. Also, note that many automobile and car seat manufacturers max out the LATCH weight limit at 40 pounds, so check your manual.
When to graduate: Most convertibles have weight limits that max out at 40 pounds and up, allowing toddlers to rear-face longer. (Note: the American Academy of Pediatrics now recommends keeping children rear-facing until at least age 2.) Once your child’s ears hit the top of the convertible seat shell or he reaches the weight limit, it’s time for a belt-positioning booster.
Phase Three: Belt-Positioning Booster
Recommended models: Britax Frontier 85, Clek Oobr, Graco TurboBooster
Details: Boosters are used to elevate a child into the proper position to safely wear a car’s seat belt. Many boosters can convert from a 5-point harness into a regular booster, enabling squirmy tots to be harnessed a bit longer. When using a seat belt with a booster, the lap belt should rest across your child’s thighs—not across the stomach—and the shoulder belt should rest comfortably across her shoulder. Always use the shoulder belt; it might look uncomfortable, but it keeps your child from lurching forward in the event of a collision.
When to graduate: Your child is ready to be taken out of a booster when she can sit still on her own, with her back against the car seat, feet on the floor, lap belt across her thighs, and shoulder belt across her shoulder.

The seats recommended above are a few of my personal favorites, but certainly not the only ones I approve.  For more invaluable car seat information, I highly recommend visiting