This is the APC Electric 18X10 RC Plane Propeller

Thin Electric
Use LPAR06E adapter rings
Includes one set of rings from LPAR06E

Pitch (inches): 10
Propeller Diameter (in.): 18
Hub Diameter: 1.25 in.
Hub Thickness: 0.49 in.
Shaft Diameter: 1/4 in.
Product Weight: 2.57 oz.
Color: GREY