The Diono Radian® 3RXT is the original 3 across All-in-One convertible car seat, trusted by over a million parents to protect their child from birth to booster (5 – 120 lb / 2.2 kg – 54 kg) Lovingly engineered with the famous Diono Steel Core and now rear facing for even longer, expect 10 years of safety from just one car seat.