What are the weight and height requirements for using the 5-point harness?

The child must weigh 10 to 22.6 kg (22 to 50 lbs) and be 71 to 127 cm (28 to 50 in.) tall, with the tops of the ears at or below the top of the headrest. The child must also be at least 2 years old. Once your child exceeds any of these size requirements, you must discontinue use of the internal harness and convert to booster mode if possible.