[xarope]

assuming this is a cr2025 then most likely 20mm diameter and 2.5mm thick => 2025

[bookofjoe]

this is the most useful thing I've learned so far this year

[jsmith45]

Yeah almost certainly talking about a CR2025.

Use of a 2025 cell would be rather irritating to me, because in my experience CR2016 or CR2032 are both more common, and it seems like it should not be hard to fit a 2032 into most keyfob designs.