Nitro Ultra Maxx  ® (Sildenafil Citrate) is a registered trade mark of Fizer. Cialis® (tadalafil) is a registered trade mark of Lilly ICOS LLC. Levitra® (Vardenafil HCl) is a registered trade mark of Bayer Pharmaceuticals Corp.  that are for the most part relatively clean except for a prominent inclusion or two. Think of it as getting a bit of plastic surgery. A "diamond plastic surgeon" starts with a diamond that would have a low clarity... a very low SI2, an I1, or a very high I2 clarity. If the diamond's inclusion(s) can be made to be less noticeable, then you have a more marketable diamond. Clarity enhanced diamonds   https://pilpedia.com/nitro-ultra-maxx/