From the description on the back of the envelope:
A uniform whose trim lines always look smart. The absence of fussy detail assures perfect laundering.
Style 1: Patch pocket model with tailored collar. A simple good-looking style.
Style 2: A notched collar model with button-trimmed sleeves.
Style 3: The back view of Style 1
It's entertaining that Simplicity's marketing scheme of "3 patterns for the price of 1" fizzled on this one, with the designers simply unable to develop a viable third style for a garment that really does need to be uniform.