For fast and simple integration of loxP-sites into large vector plasmids at any intended position (for generation of transgenic mouse models). The included loxP-PGK-gb2-neo-loxP cassette is designed to allow neomycin / kanamycin selection in prokaryotic and eukaryotic cells. It combines a prokaryotic promoter (gb2) for expression of kanamycin resistance in E.coli with a eukaryotic promoter (PGK) for expression of neomycin resistance in mammalian cells. The included 706-Cre expression plasmid allows Cre recombination in E.coli. This kit can also be used to work on bacterial artificial chromosomes. High Red/ET efficiency plus convenient removal of the Red/ET Recombination protein expression plasmid pRedET after recombination.