The 2006 Lexus RX 400h is a hybrid vehicle that has been reviewed by several outlets, with some noting its quiet and zippy performance. It appears to be one of the earlier mass-produced hybrid vehicles from Lexus, with some sources suggesting it may have been the first. The model has undergone long-term testing and has been compared to other hybrid vehicles, including later models such as the 2017 Lexus RX 450h.