the most simplest nipple correction cups is great for correction of flat or inverted nipples . Enjoy powerful suction,you worth to buy it!
size:
small:Diameter 0.7 inch
middle:Diameter 1.1 inch
large:Diameter 1.5 inch
How to use:
1.Place on the nipple
2. Hold in place with one hand while twisting the knob with the other hand clockwise
3.to Release, hold it with one hand while twisting counter clockwise with the other hand.