Vintage M&S (Marks & Spencer) light blue, short sleeve (possibly cap sleeve), button through shift dress in size 12. I'd say it was a sort of air-force blue.
Round neck, short sleeves, and button closures down the front and a criss-cross strap detail at the waist (back).
Viscose / Linen mix.
Label states professional cleaning but I find that a gentle/delicates wash setting is fine with most items labelled like that these days bearing in mind that this is a vintage dress and washing machines have loads more settings options now than when this dress was bought.
Was knee length on me (5'8") but the measurements are :-
neck to bottom hem = 41"
armpit to armpit = 18" (label states to fit bust 35")
label states to fit hips 37"
From a smoke free and pet free home