Child Safety Seat Mat Cushion Adjustable Stroller Seat Pad Size S for 6 months-4years baby, under 36pounds Size L for 3 months-6years baby, under 58pounds   Note: it is best not to use it on high-speed cars. We recommend that it be used in non-motorized products such as electric vehicles, two-wheelers, and electric vehicles. Because it is not a child safety seat that complies with traffic laws.