Infiniti RFID Access Key System

The 2009 Infiniti FX50S is reviewed and it is available with an RFID-enabled smart key system. ...

... "FX features Nissan / Infiniti's Intelligent Key system, which lets you lock and unlock the doors without removing the key from your pocket, simply press a tiny button on the door handle while in range with the RFID smart key. " ...

Via CNET: 2009 Infiniti SUV

2009 Infiniti FX Specifications: "Infiniti Intelligent Key with Illuminated Push Button Ignition ... "