A 5'-truncated duplication of SxlM1,fPd-w+mC-B located immediately centromere-distal to cm. This hop brought with it a 5'-truncated duplicated version of SxlM1 (wild-type for Sxlf4, extending from the original site of the progenitor insertion to beyond the most distal Sxl 3' end, leaving an intact SxlM1 allele behind in cis to complement Sxlf4.