Three position adjustable crotch strap (3.5, 5, and 6 inches from the back of the seat) and three position adjustable hip straps makes the Sonti a very adjustable rear facing only seat that fits both little and big infants.
Extra grip lockoff on the car seat base works helps installing with the vehicle seat belt by not having to worry about how your seat belt locks. Just push the black tab on the end of it out of the way and swing the arm up. Then buckle and pull all the slack out of the belt (don’t tighten as it makes the lock off near impossible to close and it isn’t necessary) and push the arm down.
Four position adjustable recline positions allows the seat to be adjusted to a wide range of recline levels to fit a wide variety of vehicles and child sizes. The knob adjuster makes the adjusting the recline as easy as the turn of a knob as well.
Multi-age recline indicator allows larger infants to sit more upright. As infants get older/larger, they tend to like to sit more upright and this allows the parent/caregiver to adjust it for the child’s preference.
Push button lower anchor connectors makes for an easier installation. You just push the lower anchors on and you’re set.
Infant insert can be used at any weight. The Sonti doesn’t come with a separate preemie insert, but the infant insert that comes with the seat does a great job of positioning even the 4 pound model we used.