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How All-in-One Car Seats Work

Types of All-in-one Car Seats

With so many types of all-in-one car seats on the market, it can be hard to choose the best unit for your child. All-in-one car seats combine an infant seat, forward-facing toddler seat and booster seat into one single appliance. These all-in-one products should not be confused with combination car seats, which only face forward and cannot be used in the child's first year of life.

It's also important to distinguish all-in-one car seats from travel systems, which generally include a car seat and base, carrier and stroller. These combination products are made primarily for infants: They allow parents to quickly transfer baby from the car to the stroller. They aren't designed to accommodate toddlers or older children.

Size, fit and weight limits are some of the most important considerations when you're comparing different types of all-in-one car seats. Before making a purchase, try installing the seat in your car to make sure it will fit. Depending on the design of an all-in-one car seat, it may accommodate infants in the rear-facing position until they reach 20, 30 or even 35 pounds (9, 13.6 or 15.8 kilograms, respectively). Experts agree that rear-facing seats are by far the safest, so many parents leave kids in this position as long as possible. If you'd like to leave your child rear-facing past the standard 20-pound mark, choose a unit with the highest possible weight limit for this configuration.

Another factor to consider when comparing types of all-in-one products is the type of restraint system. Harness systems are considered safer and more versatile than older shield or T-bar restraints, which are generally being phased out by most manufacturers. Five-point harnesses, which connect at the baby's hips, shoulders and between the legs are also thought to be safer than three-point models, which skip the connections at the hips.

When comparing harness systems, be sure to check the weight limit for each model. Once the child is placed in the forward-facing position, the harness can restrain him or her until a body weight of between 40 and 80 pounds (18 and 36 kilograms), depending on the model. Once the weight limit is reached, the child must use a standard seatbelt and booster seat. Many parents prefer to keep their child in a harness for as long as possible for added safety. If you'd prefer to stick with the harness, look for a unit that's rated to a higher weight limit than the standard 40 pounds (18 kilograms).

Just as home appliances made from stainless steel are hard to resist, parents may also have trouble skipping past car seats covered in lush fabrics in lieu of a more practical model. While safety should be your No. 1 priority when choosing an all-in-one car seat, it's hard to ignore aesthetic appeal entirely. Considering you'll be stuck with the same car seat for eight or more years, it makes sense to choose a unit that's both attractive and functional. You can also look for covers and pads to change the look of the seat or hide stains and spills over time.