Delicate Pale Blue, Grey and White Nylon Top. 
In very good vintage condition. 
No makers/sizing labels so possibly handmade. 
Great turn collar with hook and eye closure. 
Long rear zip fastening. Partially lined at top.
Would suit petite frame.  
Measurements laid flat:
Pit to Pit: 17"
Bust: 17"
Waist: 17.5"
Hips: 18.5"
Length from collar: 22"