2.64V threshold — matching the supervisor to the rail
That threshold is set for 3.0V nominal rails — the 2.64V trip point gives enough headroom to catch a brown-out before the downstream logic starts to misbehave, but not so high that it triggers on normal ripple. The reset output is active-low, push-pull, so it drives the processor's reset pin directly without needing an external pull-up resistor.
10 ms minimum reset timeout — settling the supply before release
That means after the supply crosses back above the threshold, the part holds the reset pin low for at least 10 ms before releasing it. If your system has a slow-start supply or a large bulk capacitor on the rail, the 10 ms window is usually enough — but if you are running a fast-boot application that needs to come up in under 5 ms, this part's timeout is on the long side.
SOT-23-5 package and temperature grade
It is not rated for the full automotive under-hood range, but it will work in cabin or chassis-mounted applications that stay within that window.
There is no last-time-buy deadline to manage, and no need to qualify a substitute for a production BOM.