OSE H Series Cleaver 2 Blade Propellers in Reverse(right) rotation, Machined out of Stainless Steel. CNC Computer machined to a high tolerance for use out of the box. No modifications are needed. Specs: Diameter options: 42, 45, 48, or 52mm Rotation: Right (See picture) 1.6 Inch pitch ratio. Shaft Size 3/16" (4.75mm).ATTENTION: Right-hand rotation. These spin clockwise when looking at them from the back of the boat. Used for twins or boats that require opposite rotation than normal. NOTE: When used with Zonda GT or similar powered, these are high amp draw. These are for a few seconds of use for drag-style use. These will push parts hard. If you are worried about burning things up, these are NOT the props for you. Go smaller or stay stock.