Low back boosters are just as safe as high back boosters, although they do offer less side impact protection. They are generally rated from 40 lbs to either 80 lbs or 100 lbs, although there are some on the market that start at 30 lbs. Low back boosters can only be used in cars that have headrests, or are tall enough that the tops of the child's ears is not above the car's seat.

Sasha in the Nania/Safety Baby Ola booster

Toby at 34 lbs and 42 inches in the same booster.