This is the APC Electric 8X4 RC Plane Propeller

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

Pitch (inches): 4
Propeller Diameter (in.): 8
Hub Diameter: 0.80 in.
Hub Thickness: 0.35 in.
Shaft Diameter: 1/4 in.
Product Weight: 0.46 oz.
Color: GREY