From Starline Product Information:
45 Auto+P is a strengthened version of the 45 Auto with the same external dimensions. A thicker web and heavier sidewall at base strengthens the case in potentially unsupported areas. This case has approximately 2 grains less internal capacity than the standard 45 Auto.
9MM+P has no difference from the standard 9mm Luger other than headstamp designation for load segregation. Due to standard case design, will handle +P pressures with no problems.