The fact that these phosphorescent nipples are a little gadget works only for a few minutes.
This can be useful in case of loss of nipple out of bed in the dark, when, seeking with a flashlight or light from the phone, we finally spot it in the dark if we do not immediately see !
I bought them after using transparent teats, so more discrete to baby's mouth, but we spent our time to lose and not to return because they blended in with the background! Oh well!