Yup. You need the Kenwood KCT-18 cable and the KCT-19 interface cable. The KCT-19 gives you a multi-pin cable that comes out of the radio to a plug. The KCT-18 will plug into KCT-19 on pin 3. KCT-18 is a yellow fused wire that will need to be attached to an ignition switched power source. The radios normal power input stays as is, hopefully fed directly off the vehicle battery.
Once you have that all wired, the radio will need to be programmed to allow ignition switched with delay option.
I've got this on my NX-700 and NX-900 in my work truck and it's set to 3 hours of delay. When I get in the truck and start it, the radios power up. When I shut the truck off, the radios will stay on for 3 hours, then power down on their own. The radio's power switches still functions and will allow me to turn the radios on/off via the front switch.
This is a great thing to have on a radio as it will keep the radio from draining your battery. I'd occasionally leave the radios on overnight and drain the battery down. I've installed this on both our personal vehicles also. My wife really likes it since she doesn't need to remember to turn the radio off.