While standard "superglue" is 100% ethyl cyanoacrylate, many custom formulations (e.g., 91% ECA, 9% poly(methyl methacrylate), <0.5% hydroquinone, and a small amount of organic sulfonic acid,[17] and variations on the compound n-butyl-cyanoacrylate for medical applications[12]) have come to be used for specific applications. There are 3 cyanoacrylate compounds currently available as topical skin adhesives. 2-Octyl-cyanoacrylate is marketed as Dermabond and SurgiSeal. n-2-Butyl-cyanoacrylate is marketed as Histoacryl, Indermil, GluStitch, GluSeal, PeriAcryl, and LiquiBand.