The BRITAX Infant Positioning Insert may be necessary for small infants to achieve a snug fit of the harness around you child. The Infant Positioning Insert has been tested and certified for use with the following BRITAX convertible car seats: ROUNDABOUT 55, MARATHON 70, BOULEVARD 70, BOULEVARD 70 CS, and ADVOCATE 70 CS.

• May be necessary for small infants to achieve a snug fit of the harness around your child
• Sled tested and certified for use with the following britax convertible car seats: roundabout 55, marathon 70, boulevard 70, boulevard 70 cs, advocate 70 cs
• For use with infants weighing between 5 and 11 lbs