The Summer Infant 3D Lite and 3D Mini are two different strollers with varying specifications. The 3D Lite is heavier at 13 pounds and can carry up to 50 pounds, while the 3D Mini is lighter at 11 pounds and can only support up to 45 pounds. Additionally, the 3D Lite has a 4-position recline seat, while the 3D Mini has a multi-position recline seat.