For some of us, the dream of a convertible car seat starts just days after baby is born, as we awkwardly struggle to buckle our tiny newborn safely into her infant car seat (usually in front of a dozen skeptical nurses). For others, that bucket seat is baby’s happy place, and we don’t think about the toddler version until he’s literally bursting out. Whether we’re in a rush or playing the waiting game, though, some time around the 1-year mark, it’s time to make the switch.

To help us figure out the when, why and how (among other things), we turned to our favorite certified Child Passenger Safety technician George Fleites, who installs car seats safely out of the Dix Hills Fire Department. Below, Fleites tells us why the best convertible car seat is “the one you’re going to use right every time,” and how to avoid being one of the 75% of parents that the National Highway Traffic Safety Administration says gets it wrong. Then check out 8 great convertible car seat picks perfect for city living.

How do you know it's time to transition your baby from an infant car seat to a convertible car seat?

Infant car seats will last from the newborn stage up to around 35 or 40 lbs. They’re always rear-facing and pretty easy to install. When baby is 1 year old, or when they’ve reached the maximum weight allowable for your seat, it’s time to get ’em out. Plus, do you want to carry that 30 lb. baby all the way to the car in your infant seat, or just plop them in the seat all ready to go? You can also buy a convertible carseat that will take a newborn, but it’s not necessarily convenient if you live in the city and are moving the infant car seat from the house to the car to the stroller.

When can they turn around facing front?

Two years, if the child has proper development and is not out of their weight range. It’s all about neck development--if they’re facing forward, they can get spinal injuries, but if they’re rear facing, the impact is absorbed by seat. A lot of moms say their child is uncomfortable facing backwards because their legs are scrunched up against the back of the seat. But a knee injury is always better than a neck injury.

Can you register for a convertible car seat and save it for a year, or should you get it when you are closer to making that switch?

Most carseats expire 6 years after the manufactured date. But car seat technology changes constantly, so a seat you like today might change design or have different instructions for use. If you plan on buying a year early, it’s ok, but I would recommend waiting to get the newest technology.

What should you look for in a convertible car seat?

Every seat sold has to meet government standards for safety. They wouldn’t be sold in the U.S. if they weren’t safe. But some are easier to use, more comfortable, or a better fit for certain vehicles. Some things to keep in mind:

  • Simplicity: The biggest thing I tell people to look for is a seat you always use the right way. There’s some great high-tech car seats, but they can be difficult to figure out how to install. No matter how high end and expensive your seat is, if you’re not using it correctly, it doesn’t do the seat justice.
  • Fit with your vehicle: A seat that’s great for one car is horrible for another, based on variations like the incline of seat.
  • Side Impact Technology: The higher end the carseat, the more cushion and side impact it typically has.
  • Harness: Since the straps should always be right at the child’s shoulder level, when your child grows, you have to move the strap. In some seats, the harness comes out of the back of the seat, so you can adjust it without even taking the seat out of the car. Others, you have to take it out every time the child grows.
  • Cushioning: If you take your kids for long 3-4 hour trips, you may want something with more cushioning. Some seats they’re basically sitting on plastic, while others have memory foam in them. You’re never allowed to put down towels or cushions between the seat and the child, so keep that in mind when thinking about comfort.

Are there any features that you wouldn't want your car seat to have?

It’s not as much about the seat as it is about the accessories, like mirrors. In heavy impact, they slide off and hit baby in the face. They’re also a distraction to the driver. If your baby is sleeping, you know they’re sleeping, if they’re crying, you know they’re crying. We don’t like hard plastic shades either--they can also fly off and hit the baby. Also, there should never be any padding that goes between baby and carseat, like those cold-weather car seat liners. Same thing with heavy clothing, like a poofy snowsuit.

How are the needs of a city parent different than a suburban parent when it comes to convertible car seats?

First of all, according to the law, if you’re bringing a baby into a taxi cab, they do not have to be in a car seat. If you want to be safe, though, you should always use a car seat. So as a city dweller, try to pick the lightest one. And since it’s not a two-second thing to put a convertible into a taxi cab, you want to do it correctly. So the best car seat is going to be the one you’re going to use right every time...the one that’s the least complicated.

Walk us through an installation. For a parent that is switching carseat from rental car to rental car, how can you make sure it's in right every time?

  1. The first thing we do as certified Child Passenger Safety technicians is inspect what the parent did, and most of the time, it’s wrong. Then we take the seat out, look at its serial number, date and model number, and check recalls. For a convertible seat, we have the child sit in the seat outside the car to adjust the shoulder harness correctly.
  2. You should never use both the latchpoints (every automobile manufactured after 2001 has to have them) and the seatbelt. If using the latches, just latch the seat into the latchpoints. If your seat is forward-facing and the child is 42 lbs., you’re going to use the seatbelt, but it has to be converted out of emergency mode (when it senses a jolt forward, it will lock up). To convert it, run the seatbelt through the back of the seat, pull all of the webbing out to the end, and listen for the click. Then you can go ahead and lock it in with the seatbelt.
  3. After the seat is good and tight, there’s a tether on back of seat. For a forward-facing seat, it’s attached to the top of the carseat and goes under the headrest, tightened up.
  4. Finally, grab the seat and push it side to side. We’re allowed 1 inch of movement, but we usually get no movement at all. You don’t want that carseat wiggling around.

Here’s some of the latest and greatest in convertible car seats.