What does "Size 15" and "Size 14" mean?

Nanodroppers come in two sizes. The size numbers ('15' and '14') simply tell you the metric measurement (in millimeters) of your eyedrop bottle's neck, right where the original cap twists on.

Size 15: This is the original Nanodropper size. It is designed for bottles with a neck that is about 15 millimeters wide. It fits the vast majority (about 90%, or 9 out of 10) of standard eyedrop bottles .

Size 14: This size fits bottles with a slightly smaller neck (about 14 millimeters wide). It adds coverage for another 7% of bottles that the Size 15 cannot fit.

Both sizes do the exact same important job! They are functionally identical and reduce the volume of a standard drop by over 60%.

Note: Compatibility information reflects physical bottle fit only and is not an endorsement for use with any specific medications or formulations. Always consult your eyecare provider to check if Nanodropper is appropriate for your treatment plan. Please refer to manufacturer guidelines for all safety and expiration information.