Physician Formula (PF) claims that this will make lashes instantly appear luscious, glamorous and dramatic, and that 100% test subjects who tried this eyeliner out saw their lashes enhanced instantly. Whatever it means by "enhanced" can be up to each of our interpretation, but for my opinion, I love this liner because it is dark, long-lasting, an it does not bother my sensitive eyes.
This eyeliner is formulated with a serum that is supposed to help lashes grow. I have short stubby lashes that seem to have grown faster and longer over the past 2-3 years which could be attributed to this liner, though I am not 100% sure. PF also claims that the product is water resistant and smudge proof. I have worn this eyeliner for years, and I can say that it is waterproof and smudge proof, however, if it were to rain and you rubbed your eyes, the eyeliner will smudge and disappear off your lids.
PH additionally claims that you can wear this liner for 24 hours. I have never tested this claim because well, I don't wear eyeliner for 24 hours, but it does last throughout a normal 8-12 hour day for me.
One of these liners will last you for a very long time. I normally go through one every 6-8 months give or take. It's like a magic pen that keeps on giving!
What I like most about this liner is the tip. The tip is a calligraphy style pen instead of those felt tip liners that dry up fast. I feel that felt tip liners can really drag on your skin and eyes, while calligraphy style liners glide easier on the skin, which allows for better accuracy.
A pro to this liner like I have stated before is how dark the liner is. I believe this liner comes in three shades: Ultra black (the one I wear), very black, and brown. I always go for ultra black, and it is really black! Take a look below. You can see that I've drawn different strokes and squiggly lines. This is a great liner for doing a winged look or any kind of look. Do note that the liner I used for the swatches is an older one that I've opened towards the beginning of autumn. It's still very black even after all these months!