Abstract: A system and components for treating aortic aneurysms includes a reinforcing graft and fittings for securing the graft to a host vessel and to branch vessels, for example the iliac and renal arteries. Combinations of fittings and rings or other compression mechanisms secure vessels or grafts frictionally, for end-end or end-side couplings. A variety of tools are disclosed for manipulating retaining rings, everting portions of grafts or vessels in the course of coupling them to fittings, and clamping fittings while positioning the retaining rings.