Composite drive shaft assembly. This driveshaft is assembled with 316 stainless steel hardware and hubs. The Max HP at a 2.0 Service Factor is 357 at 1,800 RPM and 298 at 1,500 RPM The max DBSE (in.) is 166 at 1,800 RPM and 181 at 1,500 RPM. Custom bores are included with purchase in the standard range of bore sizes. Larger bores are available at additional cost.