What are the weight and height requirements for using the Graco car seat as a booster without the harness?

Your child must weigh between 30 to 100 lbs (14 to 45 kg) and measure between 35 to 54 inches (89 to 138 cm) in height. The child's ears must be below the top of the booster seat. If a child is between 30 and 40 lbs with shoulders below the upper harness slots, use of the built-in harness is highly recommended for as long as it is suitable and comfortable. (Page 10)