text: A Type V-K system was originally characterized from a cyanobacteria, Scytonema hofmanni, and contains a single Cas effector, Cas12k, that functions with a tracrRNA. This system functions similarly to Tn7 but does not have a TnsA protein which can result in off-targeting and chimera formation during over-expression. The Cas12k and tracrRNA complex bind to the target site and TnsC is polymerized directly adjacent prior to TniQ attachment and TnsB recognition and integration. While these systems use traditional tracrRNA characteristic of Type II CRISPR systems, they can also target with short crRNA located adjacent to the transposon end. Type V-K spacers preferentially target locations near tRNA genes, but other sites have been observed in these short crRNA guides which have been acquired by non-traditional means.