This is the GrimRacer L40x57 Lifter Metal Boat Propeller from AquaCraft.
FEATURES: Constructed of high quality Copper-Beryllium-Titanium material that
is rigid but not brittle and can be sanded and shaped with less
effort than Stainless Steel props
Copper-Beryllium-Titanium material stays sharper longer and is less
prone to dulling and chipping
True center bore hub with raised letters and numbering for easy
Tumbled to remove any excess cast flashing
INCLUDES: GrimRacer L40x57 3-Blade High Lift Metal Boat Propeller
REQUIRES: Installing on propeller shaft
SPECS: Diameter: 40mm (1.57")
Pitch: 57mm (2.2")
COMMENTS: CAUTION: Wear eye protection when tuning and working on metal
Wear a respirator when filing or sanding these propellers. The dust
produced is hazardous to your respiratory health.