The First Years Jet Stroller easier for you, more comfortable for your baby. Finally a stroller that is durable and, yes, it really will comfortably fit your little one up to 50 pounds. The wider seat base means a more comfortable ride for your child, which will keep them in their seat longer. The larger wheels (6" diameter), all eight of them, allows your Jet stroller to glide over any surface. Worried about keeping your little one in their seat. The addition of the five point harness means your little one is securely seated.