Full-size rear seat for child too young to use the rear bench seat and the standing platform;Easily installs onto the existing rear bench seat and stroller frame;Multi-position recline, 5-point harness, and folds up with the stroller;Compatible with Caboose Graphite, Caboose Ultralight Graphite or Big Caboose Graphite models only;Minimum age 6+ months, max weight: 45 lbs.