May be necessary for small infants to achieve a snug fit of the harness around your child. For use with infants weighing between 5 and 11 lbs.
Sled tested and certified for use with the following BRITAX Convertible Car Seats: ROUNDABOUT 55, MARATHON 70, MARATHON 65, BOULEVARD 70, BOULEVARD 65, BOULEVARD 70 CS, BOULEVARD 65 CS, ADVOCATE 70 CS, ADVOCATE 65 CS