I bought this to connect two torque limiter shafts at the end of the rotation limiter. Both ends of the bushing are part of a shaft with a set of set screws. The second shaft must be mated to the outer casing of this coupling which has no assembly tool other than pushing it into the bore behind the knurling. It turns out that there are several mounting options from a manufacturer from another country. So I have a choice: throw the part away, find a suitable replacement, or custom build a fixture for my application. Even with the manufacturer's passport it was confusing. Please check the applications before purchasing this item.