Four toothed castle nut socket for Kawasaki swinging arms, which allows for loosening and tightening of the swing arm nut. Application: Kawasaki ZX6R 600 (2005 – 2010), ZX6RR (2005), ZX6R 636 (2005 – 2006), ZX10R (2004 – 2010), Z1000 (2010), GTR 1400 (2008 – 2010), ZZR 1400 (2006 – 2010).