Marnetic Car Booster- Can it be used in the USA?

I came across this device which is best described as a booster seat, but is described as a “car cushion seat” or “child safety car portable seatbelt” amongst others. I saw it on Pinterest, but apparently it is a real item as you can also buy it at Walmart. I am traveling in August and I thought this might be a cool alternative to bringing our car seat. Our son will be 12 months old and he is a big boy, so will likely be out of the infant seat. However, I am not sure if this is legal in the USA, or if it meets the federal safety standards, or if it meets the state safety standards of Tennessee? I know in my state it wouldn’t just because under two is rear facing. Anyways, does anyone know anything about this product, its safety, its legality or have any experience with it?