Mercruiser 93322A12 Extension 6" block kit. Includes 4-full flow riser gaskets, mounting bolts to attach to manifold, and mounting brackets for accessories that are attached to the extension blocks. Bolts to mount exhast elbow are not included. order (8)10-43749 mounting bolts (if needed) for exhaust elbow. Replaces older Mercruiser part numbers 93322A3, 93322A4, 993322A6, 993322A7.