A truly excellent hair hardener! For thin, weak nails. Triple strength polymers, formulated with calcium and protein, form a protective shield to increase nail thickness for maximum reinforcement.As written up in O magazine, This is what they say about Daby Nail Hardener...The nail hardener we swear by — you know what the model in this picture did to get strong, beautiful nails? Not a thing. That's right: No dish-washing or tub scrubbing, and definitely no envelope opening or soda can popping. For those of us without a manservant in our future, we've found another way to protect against peeling and breakage. A coat a day of Daby Nail Hardener, a clear polish that prevents dehydration with nitrocellulose (but no stinky formaldehyde), has left our once-brittle nails impervious to abuse — and verging on model material.