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.

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