It's 0.0015, that's 1.5 to 2.5 thousandths, or 15-25 "tenths" as they're called.

That's not a particularly tiny gap in the machinist world, it's large so that you can pump viscous oil in it and deal with a wide variety of temperature changes.

25 thousandths would be sloppy, a nominal clearance hole for a 1/4x20 bolt is about that much.