I can't say enough nice things about this unit. With 12v being the very bottom of its input voltage spec, I wasn't sure how it would perform in an automotive application, but it's happy to 10v and below, turns out.It gets a little warm in operation, so don't wire it up where that would cause battery drain, but as a shutdown timer that kills its own power, it's fine. (Program E, with some diodes to let it power itself up in the first place.) All the programs are useful too, I'm gonna start keeping a few of these around for general purposes.The time setting dial isn't super accurate; the range between 1% and 10% is considerably smaller than it looks. If you need very long times, this can be difficult to test, but the percentage applies regardless of which decade interval you've set. So the workaround is to find a short interval and test there: Say you need a 7-day delay, which you'll set as 70% of the 10d interval. Instead, set it for the 10s interval and tweak the percentage until you get a 7s delay. Then just flip over to the 10d interval and you should be good!