I sure was curious and skeptical about this product when it arrived. I am impressed though I've recently gotten the balls to shave my head down to 2-4 mm so the Toppik only has so much hair to build onto - even then I think it works well. I have tons of vellus hairs where I show most skin yet Toppik covers it suprisingly well - I just get nervous thinking about rainy days, or sweating...