In my experience appropriately sizing Philips is basically impossible unless the screw itself is marked. The #2 is way more common it seems so that helps with t

In my experience appropriately sizing Philips is basically impossible unless the screw itself is marked. The #2 is way more common it seems so that helps with the default but if you know it isn’t #2 then you are screwed (har har) because many different size drivers will ‘fit’ and ‘work’.