The sphincter muscle is an annular muscle surrounding and able to contract or close the anus. Label reads, "Weez gessin' it alls startud when gra'ma wuz in tha outhouse, yellin', cussin', and bangin' round sumthum feerce. Shur nuff, earlier she'd gottin' inta a new batch of sauce weez jus' brewed up. Und that's where tha name cums from, cuz her 'ole sphincter wuz on fire, and und she shur was scremin'!"