Kastar 6530 Lower Rocker Box Wrench 7/16" for Twin Cam This extra long reversible ratcheting box wrench is used to install/remove the lower rocker box on Harley-Davidson motorcycles with Twin Cam engines (1994 1999). A special 7/16" socket protrudes out of the wrench to reach the application. Vinyl grip provides a comfortable ergonomic grip and prevents the wrench from scratching or marring the bike. Extra long reversible ratcheting box wrench used to install/remove the lower rocker box on Harley-Davidson motorcycles with Twin Cam engines (19992006). Vinyl grip prevents the wrench from scratching or marring the bike.