High Back Booster????

At 4 I would still use a harness. My 4 1/2 yr old is stil happy using the harness in his graco nautilus.

I would still keep him in a harnessed seat at only 43 pounds. My son is 3.5 years 42 inches and 45 lbs and still harnessed. It is so much safer. Plus at that age they do not really have the maturity to understand the importance of sitting up straight and keeping the belt over their shoulder the entire time. What if he falls asleep, he won't be properly restrained by the belt. Just a thought.

my personal thought is to use a high back booster with the 5 point harness on it so you can use the harness as long as possible. my daughter is your son age and weight and we still use the 5 point harness on her except for the travel seat that is the 2 piece booster that just uses the seat belt

5 point harness. My son is 8 and weighs 58 pounds and he is in the Britax Frontier which is good until he is 100 pounds. It also converts into a booster. They are much safer. If the lap belt is not correct, which it usually isn't in younger children and you are in an accident, it can actually eviscerate your child. Not pretty. We do use the Britax high back booster when he travels with my husband so we don't have to move the car seat, but there are great safety features. You only get one of them, so keep them as safe as possible for as long as possible. Unfortunately, it isn't about your driving, but someone elses.

It depends on how old the child is. I had a one piece high back booster until my child was five (sturdier and plenty of support) and then switched to a two piece until eight. It was thinner and made her feel like a big girl. Since she had to use one until eight (state required) I only had to remove the back when she was "embarrassed" of her booster.

my daughter is 3.5 and wieghs 32 pounds. she's in a booster because she's so tall for her age (39 inches). She does great with the booster - we have an evenflo, but i don't remember what model it is. She keeps it over her shoulder all the time, even on longer car rides. it has cupholders so she can put her cup there, or a cup with snacks in it. we love it, and she loves it.

My almost 7 year old just started using one when she could sit still, sit properly, and buckle it tightly herself. I would never put a 4 year old in a belt positioning booster. Mine has the britax frontier, only carseat she will ever need, five point harness (safest) to 85 lbs then belt positioning to 120 lbs.