With a Landoll weight ring. 11 pound steal ring that bolts directly to the fly-wheel to add inertia and help smooth out a rough idling engine. On my wood prop setup the change was very noticable. But I decided to switch to FP metal prop becuase of all the rain here in the Florida summers. Includes bolts and metal locknuts, like new $100.00, I pay shipping to purchasers in USA.