Johnson Evinrude Impeller | Sierra 18-3006 Sierra 18-3006 Johnson Evinrude Impeller Diameter 2-3/4 in. Depth 1/2 in. Shaft diameter 3/4 in. 6 Blades Material: Neoprene Replaces Johnson/Evinrude 775521, 378891 Replaces Mercury 802319 Replaces Mallory 9-45217