Esabel.CWomens Button Down Shirts Long Sleeve Regular Fit Stretch Work Blouse

I am looking for a black button down blouse that will stay tucked in for waiting tables

How long is this shirt? Can you wear it with leggings?

Since it’s 97% Cotton will it shrink when I wash it? I usually like a little bit loose fitting.

I’m 93lb but 28ddd slightly broad shoulder and 21” waist what size should I get?