It's a rather simple "install" process, however, it must be done everytime you use your turn signal and don't turn hard enough for it to automatically turn off.
Additionally, some models will turn themselves off after they've been on too long. Of course, sometimes you need it on a long time.
Imagine a freeway with 2 lanes merging into 3 to end up with 5 and an exit ramp on the right and a right turn to be made at the end of the exit ramp.
It was the only situation where my Chrysler would decide I'd had my blinker on long enough even though I hadn't.