TK2568 31-Spline Input Shaft Swap Kit for new 24-spline or 34-spline transfer case assemblies. When a new 24-spline or 34-spline transfer case assembly is the only option and you need a 31-spline, purchase the 24-spline or 34-spline transfer case assembly plus this Input Shaft Swap Kit to easily turn your new transfer case into a 31-spline. Works for NV271F or NV273F transfer cases.