Blue lingerie slip no tag no size Pre-Owned guessing size M/L see measurements

Slip has one stain (see photo).

Measurements:
Shoulder strap to bottom of slip is 30.5 inches in length.
Armpit to armpit is 16 inches across.
Shoulder to front cleavage is 11 inches in length.
Shoulder to back cleavage is 14.5 inches in length.